Heat. Energy and Control. An Integrated Unit for Grade 7. Written by: Griffin, Moore, Desmond, Micacchi, Morrow, Tallman, Tonner, Turnbull,...

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1 Heat Energy and Control Including: Heat: An Introduction Measuring Temperature Heat Capacity States of Matter and the Particle Theory Heat Transfer Energy Transformation and Heat Systems Culminating Task An Integrated Unit for Grade 7 Written by: Griffin, Moore, Desmond, Micacchi, Morrow, Tallman, Tonner, Turnbull,... Length of Unit: approximately: 20.6 hours October 2001 Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:06:53 PM

2 Heat Energy and Control An Integrated Unit for Grade 7 Acknowledgements The developers are appreciative of the suggestions and comments from colleagues involved through the internal and external review process. Participating Lead Public School Boards: Mathematics, Grades 1-8 Grand Erie District School Board Kawartha Pine Ridge District School Board Renfrew District School Board Science and Technology, Grades 1-8 Lakehead District School Board Thames Valley District School Board York Region District School Board Social Studies, History and Geography, Grade 1-8 Renfrew District School Board Thames Valley District School Board York Region District School Board The following organizations have supported the elementary curriculum unit project through team building and leadership: The Council of Ontario Directors of Education The Ontario Curriculum Centre The Ministry of Education, Curriculum and Assessment Policy Branch An Integrated Unit for Grade 7 Written by: Griffin, Moore, Desmond, Micacchi, Morrow, Tallman, Tonner, Turnbull,... Thames Valley District School Board Based on a unit by: Griffin, Moore, Desmond, Micacchi, Morrow, Tallman, Tonner, Turnbull,... Thames Valley District School Board This unit was written using the Curriculum Unit Planner, , which Planner was developed in the province of Ontario by the Ministry of Education. The Planner provides electronic templates and resources to develop and share units to help implement the new Ontario curriculum. This unit reflects the views of the developers of the unit and is not necessarily those of the Ministry of Education. Permission is given to reproduce this unit for any non-profit educational purpose. Teachers are encouraged to copy, edit, and adapt this unit for educational purposes. Any reference in this unit to particular commercial resources, learning materials, equipment, or technology does not reflect any official endorsements by the Ministry of Education, school boards, or associations that supported the production of this unit. Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:06:53 PM

3 Unit Overview Heat Page 1 Energy and Control An Integrated Unit for Grade 7 Task Context In today's world, non-renewable heat sources are being depleted. It is important to consider ways to conserve and recycle excess and waste heat as well as look at new, alternative sources of heat. Working in groups, students will apply their knowledge of heat properties to construct a lunch box that maintains functional temperature zones and does not allow heat transfer between the zones. Task Summary "HOW IS HEAT RELATED TO EVENTS THAT OCCUR IN EVERYDAY LIFE?" The foregoing question provides the central focus for this unit. Students will learn more about the transfer of heat, the capacity of certain materials to hold heat, and how the properties of heat can be applied to natural and human-made environments. Culminating Task Assessment In the culminating task students will apply their understanding of heat to the design and construction of a lunch box that maintains functional temperature zones and does not allow heat transfer between the zones. Links to Prior Knowledge In previous years, students have investigated numerous concepts related to energy. In the course of these investigations they have developed an understanding of the different ways energy is used in our daily lives, the sources of energy (e.g., wind, moving water, mechanisms, electricity, light and sound), the relationship between force and energy, and the methods used to conserve energy. Considerations Notes to Teacher 1. Heat Sources Through the unit specific heat sources are suggested for use in the activities. Below is a list of heat sources and the advantages and disadvantages of their use. HOT PLATE: constant source of heat that may be regulated with the dial. It must never be left unattended because the porcelain top gets very hot and stays hot after the hot plate is shut off. Hot plates are expensive so students should be careful not to damage the porcelain top through over use and improper cleaning. Plugging more than one hot plate into the same receptacle may blow the breaker, so check with the custodian before doing so. BUNSEN BURNER: needs a gas source which is rarely found in Elementary classrooms. Be careful of gas leaks and valves not being turned off properly. STERNO CAN: gives off constant heat and can easily be put out by covering the opening with the lid. Be careful not to leave the sterno cans unattended and ensure that the area is clear of clutter. Sterno can be purchased at camping or outdoor stores and require matches or a lighter to light them. HEAT LAMP: provides a constant source of direct heat. Ensure that the outlet is capable of supporting the wattage required. Substances such as fabric and paper can catch on fire if left near a heat lamp too long. Never leave a heat lamp unattended. CANDLES: give off little heat, may tip over easily and drip wax on surfaces. They are NOT recommended for this unit. SUN: dependent on the weather and difficult to harness and control. Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:06:56 PM Page A-1

4 2. Safety Issues Safety in the science lab is very important. This unit employs investigations which require students to use various heat sources. It is critically important to establish specific and appropriate guidelines for the use of heat and to discuss the behaviour expected during hands-on activities. A safety contract is strongly recommended. An example has been included in the blackline masters (Safety Contract, BLM 7.1.1). Once the safety contract is established, share this information with administrators and parents, so there are open lines of communication and so everyone is aware of the expectations. An established policy which is supported by everyone involved is beneficial. A useful safety resource written for use in elementary schools is "Be Safe" produced by the Science Teachers' Association of Ontario. When lighting heat sources such as candles and burners, it is recommended that the teacher always handle the matches or lighter to light the heat source. Individual teachers and schools can establish routines and guidelines that meet their needs. 3. Unit-Wide Resources I.N.S.I.T.E. Method: The term "I.N.S.I.T.E. method" is used in several subtasks. This method of inquiry will help guide students in their investigations. This method is used in a number of subtasks in the unit. Details are provided in a unit wide blackline master (I.N.S.I.T.E. Method, BLM 7.uw.1). A poster which may be enlarged and posted in the classroom (I.N.S.I.T.E. Method of Inquiry, BLM 7.uw.2) is also provided. The Inquiry/I.N.S.I.T.E. rubric (BLM 7.uw.3) may be used to evaluate student work. You will also find the "S.P.I.C.E. model", the model for the design process, available in the unit wide resources (S.P.I.C.E. Model of Design, BLM 7.uw.4). 4. The Science and Technology Journal and the K.I.L.E. approach Science and Technology journals give students the opportunity to construct their own understanding; to put into their own words what they are learning. They can link the observations that they make with the knowledge that they bring with them. Verbalizing ideas, both orally and in writing, is an important step in internalizing new information. Explaining and describing experiences helps learners to make connections between concepts and ideas. It also allows the teacher to track and assess the students' understanding and it provides an opportunity to correct any misunderstandings that the student may have. The K.I.L.E. approach is used throughout this unit as a way of assessing student's learning in their science journals. In the first subtask students will be asked to write down things they know about heat (K) and interesting questions, thoughts, or ideas (I) related to the topic. In the remainder of the subtasks students will be asked to add information about what they learned (L) in their journals and provide examples of situations in which they have experienced this (E). This will provide the teacher with an opportunity to assess students' knowledge, and communication skills as well as their ability to relate learning to the outside world. An assessment rubric for the students' written work using the K.I.L.E. approach in their science journal is provided as a blackline master (Science and Technology Journal Rubric, BLM 7.uw.5). In order to assist students to be successful communicators in science and technology, students will need to see models of good journals and will need lessons on journal writing. Suggested strategies are: a) Explaining Criteria - The teacher explains the criteria for writing a journal entry by demonstrating each statement using examples from class journal entries. Next students can use the criteria to assess a piece of scientific writing. The teacher displays the writing on an overhead or chart paper and, as a class, the students discuss the piece of writing. b) Independent Writing - When students have had many experiences in shared writing, they can record their ideas independently. The teacher can use a rubric to assess the first entry and provide feedback to individual students in order to improve science and technology writing skills. The information from this assessment could also be used for the development of class demonstrations in a specific area. Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:06:56 PM Page A-2

5 5. Integration Each activity is designed to build skills and concepts which will be demonstrated in the summative task. Although these lessons may be taught independently, integrated learning opportunities in other subject areas may be addressed simultaneously. Science is a form of knowledge that seeks to describe and explain the natural and physical world and its place in our universe. Technology is both a form of knowledge that uses concepts and skills from other disciplines (including science) and the application of this knowledge to meet an individual need or specific problem. Inherent in these studies is the need to both research and communicate ideas and findings, whether through specific use of scientific and technical vocabulary, or through the use of diagrams or illustrations. The study of science and technology is an opportunity for students to reinforce and extend expectations in other subject areas. When unit or term planning, teachers may wish to take advantage of opportunities to address and assess expectations from other curricula. 6. Assessment In this unit, a variety of assessment strategies and recording devices have been included. The assessments provide the teacher with information on the development of students' skills in all areas of the achievement scale as outlined on page 13 in The Ontario Curriculum, Science and Technology document. Assessment Accommodation Strategies 1. Consult Individual Education Plan and adapt the assessment format (e.g., oral, practical demonstration, interview, construction, tape-recorded test) to suit the needs of the student. 2. Allow the student to write the main points and expand verbally. 3. Allow additional time, when required for completion. 4. Read or clarify questions for the student and encourage student to rephrase questions, in his/her own words. 5. Provide highlighting of key words or instructions for emphasis. 6. Use several assessments to establish ability. 7. Use of Blackline Masters Included in this unit are a large number of blackline masters. Due to the nature of the scientific material covered in the unit and in order to meet the needs of teachers with various backgrounds, it was decided to include a broad range of blackline masters. Instead of photocopying all blackline masters the following strategies could be used: -Have students recreate the blackline master as a science journal activity or in a group assignment. -Recreate blackline master on a bulletin board (e.g., vocabulary/definition and fact bulletin board). -Recreate blackline master as a wallchart or on chart paper. -Copy blackline master on acetate and use it on an overhead projector. 8. Classroom Accommodations All accommodations must take into account the student's Individual Education Plan. All of the tasks and activities are designed to accommodate the needs of students at different levels of abilities. Many of the activities include pictures and/or examples of a step-by-step process. These may be used at the discretion of the teacher for some or all students. As well, teachers can easily adapt the activities to allow for open-ended, student-directed tasks. Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:06:56 PM Page A-3

6 Heat Energy and Control An Integrated Unit for Grade 7 List of Subtasks Subtask List Page Heat: An Introduction This subtask provides an introduction to the unit Heat. As a baseline measure of what the students already know about the topic, they will make a K.I.L.E. entry in their science and technology journals prior to the introductory lessons in this subtask. Students will view a video which presents a general overview of the topic and will review and sign a safety contract which outlines safe science and technology procedures. Measuring Temperature During this subtask, students will investigate how temperature is measured and will practise taking the temperature of a variety of items. Heat Capacity Students will investigate the difference between heat and temperature. They will compare the amount of heat in different volumes of a given liquid and in different masses of a given solid. By noting the rate of temperature change they will be able to make some generalizations about the heat capacity of common materials. States of Matter and the Particle Theory Students will examine the three states of matter and will compare the motion of particles in a solid, liquid, and a gas using the particle theory. Heat Transfer In the previous subtasks students were introduced to the Kinetic Molecular Theory and the fact that when substances are heated, the particles in the substances speed up and begin to collide. In this subtask, students expand this understanding by examining how heat is transferred within a substance. Note: All matter (solid, liquid and gas) has some level of conductivity, however, solids are better conductors than liquids or gases so only solids will be used in the experiments in this subtask. Energy Transformation and Heat Systems Students will explore the relationship between heat and energy transformations. Students will explore everyday items that produce heat as a desired energy form, or as a byproduct, and will be introduced to sensory systems that manage or control heat energy. Culminating Task In the culminating task students will apply their understanding of heat to the design and construction of a lunch box that maintains functional temperature zones and does not allow heat transfer between the zones. Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:01 PM Page B-1

7 Heat: An Introduction Heat Subtask 1 Energy and Control An Integrated Unit for Grade 7 50 mins Description This subtask provides an introduction to the unit Heat. As a baseline measure of what the students already know about the topic, they will make a K.I.L.E. entry in their science and technology journals prior to the introductory lessons in this subtask. Students will view a video which presents a general overview of the topic and will review and sign a safety contract which outlines safe science and technology procedures. Expectations 7s65 7s73 7s70 formulate questions about and identify needs and problems related to heat (e.g., interactions involving energy transfers), and explore possible answers and solutions (e.g., identify the steps that could be followed to test the effectiveness of the heating system in a home that uses solar energy); identify different forms of energy that can be transformed into heat energy (e.g., mechanical, chemical, nuclear, or electrical energy); recognize heat as a necessity for the survival of plants and animals; Groupings Students Working Individually Students Working As A Whole Class Teaching / Learning Strategies Brainstorming Discussion Response Journal Assessment Assessment Strategies Response Journal Assessment Recording Devices Teaching / Learning Part A: "K.I.L.E. method" Introduction and Initial Entry in Science Journal (20 minutes) Note: Please read "Safety Guidelines" in Notes to Teachers before beginning this unit of study. 1. Introduce students to the K.I.L.E. method explaining that they will use this method as a guideline when making science and technology journal entries throughout the unit. An explanation of the K.I.L.E. method can be found in the unit-wide notes. 2. Introduce the subtask by conducting a brainstorming session to generate a list of words or phrases associated with the topic Heat. Copy them onto chart paper as they are generated. After reviewing the brainstorming list, tell the students that before beginning the study of Heat, they will determine what they already know about this topic. 3. Ask students to write the title, "What I Already Know about Heat" on the first page of their science and technology journals. For their first entry have them record all they know about Heat under the title. To get started they may wish to refer to the brainstorming list. Allow ten minutes for this task. Briefly discuss the entries, encouraging students to share any thoughts or questions they might have. Ask them to record any personal thoughts, ideas or questions about Heat in their journals, then collect the journals. You might want to remind students that they have used the first two stages (K and I) of the K.I.L.E. method. 4. Using the journals, generate a sample list of what the students have indicated they already know about Heat and copy this list on chart paper for posting in the room. Similarly, generate lists questions about Heat that the students have included in their journal entries. Post the charts in the room and before the next class Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-1

8 Heat: An Introduction Heat Subtask 1 Energy and Control An Integrated Unit for Grade 7 50 mins discuss the charts with the students. Indicate that throughout the unit, the charts will be referred to and facts will be confirmed or proved to be inaccurate and questions raised will be addressed during their study of Heat. PART B: The Safety Contract (10 minutes) 1. Provide each student with a Safety Contract (BLM 7.1.1). Review the contract with students, discussing each safety item to ensure students have a clear understanding of all the "safety rules" listed on the contract. 2. Have the students complete the student information section and sign the contract. Teachers should collect the contracts, verify that the students have completed them properly and then sign and date the contracts. The contracts may be kept in a teacher file or returned to the students for filing in the front of their science and technology journals. If the contracts are returned to students, teachers may wish to keep a photocopy for their records. PART D: Heat Energy: Video (20 minutes) As a general introduction to the unit show a video on Heat Energy. Adaptations Teachers are encouraged to: - involve the student in setting goals for work completion; - encourage risk taking; - provide varied opportunities for peer and/or group interactions (e.g., cooperative learning, sharing); - teach visual strategies for journal writing and/or note making (e.g., use of diagram/picture to represent content); - provide advance organizers to structure content (e.g., outlines, subtitles, paragraph frames); - encourage the use of lists, advance organizers, personal planner for personal organization; - allow opportunities for alternatives to writing (e.g., graphic representations, drama, media presentations, timelines, collages). Resources BLM blm cwk Notes to Teacher Safety Guidelines: Students must understand the dangers of working with heat sources. They must know and follow the safety guidelines provided in order to minimize the risk to themselves and others. Before beginning the unit, review the safety guidelines outlined in the Safety Contract and firmly establish the safety procedures/routines you expect students to follow throughout the course of this unit. Teacher Reflections Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-2

9 Measuring Temperature Heat Subtask 2 Energy and Control An Integrated Unit for Grade 7 75 mins Description During this subtask, students will investigate how temperature is measured and will practise taking the temperature of a variety of items. Expectations 7s77 7s67 identify the purpose of the specialized features of various instruments that are used to measure temperature (e.g., temperature probes provide accurate continuous readings); use appropriate vocabulary, including correct science and technology terminology, to communicate ideas, procedures, and results (e.g., state the boiling and freezing points of water, room temperature, and body temperature in degrees Celsius; correctly use the terms heat conductor and heat insulator); Groupings Students Working As A Whole Class Students Working In Pairs Students Working Individually Teaching / Learning Strategies Demonstration Direct Teaching Working With Manipulatives Assessment Assessment Strategies Exhibition/demonstration Assessment Recording Devices Anecdotal Record Teaching / Learning PART A: Measurement Tools and Scales (30 minutes) 1. Ask the students to identify the most common tool used to measure temperature (a thermometer). Write the term on the board. Note: Many scientific terms come from other languages. Thermometer is such a term; The prefix thermo- comes from Greek thermos, meaning warm or hot and the suffix -meter comes from the Greek metron, meaning "to measure". 2. Using the brainstorming technique, have students identify the different ways and places they see thermometers being used. See how many different kinds of thermometers they can name. Record their responses on chart paper. Remind students that many items used to "regulate" or "control" temperature have a built in thermometer, even though the thermometer may not be visible. Have students list places where thermometers may be located such as: - outside the house - in a swimming pool - in the thermostat of a room - in an oven - in a car (on the dashboard -- could measure the temperature inside the vehicle, or inside the engine) - in a refrigerator - in a hot tub - in a hospital - in a laboratory (liquid nitrogen tank) - in a steel mill 3. Discuss the similarities and differences in these types of thermometers. The students should be able to Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-3

10 Measuring Temperature Heat Subtask 2 Energy and Control An Integrated Unit for Grade 7 come up with answers that include: 75 mins - some measure very familiar types of temperatures (e.g., the outside temperature) - some measure extremely hot temperatures - some measure extremely cold temperatures - the output or readings of the temperature may be displayed in a different manner (liquid in a graduated scale, digital display, metal strip movement, dial movement) 4. Distribute the blackline master, The Measurement of Heat (BLM 7.2.1). Identify the types of substances used in thermometers and discuss the reasons they are used. Examine the brainstorming list to see if the students can identify different types of thermometers. 5. In order to measure temperature, a unit of measurement is required. The most common scale for the measurement of temperature is the "Celsius" scale. The scale is based on the freezing point of water and the boiling point of water, both of which are constant. Other scales have been included on the blackline master. The concept of "Absolute Zero" is also explained in detail on page 2 of BLM 7.2.1, The Measurement of Heat. Identify the different temperature scales, and discuss the concept of Absolute Zero. PART B: Appropriate Handling of Thermometers (5 minutes) 1. Thermometers are required to conduct experiments related to heat. Since thermometers are fragile, they can be easily broken. Urge students to handle thermometers with care. 2. Some guidelines for handling a thermometer include: - Never leave a thermometer unattended when conducting an experiment. - Ensure that it cannot roll off the work surface. - Never use it as a stirring rod. - Store it in a safe place when it is not in use. 3. Ensure students know the proper procedures for handling thermometers or other lab equipment that get broken or damaged. PART C: Taking Temperatures (40 minutes) 1. Demonstrate how to handle a thermometer properly, and how to accurately take and record the temperature of a substance. Demonstrate how to take the temperature of a beaker of water: Hold the thermometer in the middle of the water immersing it half way in the glass of water. Do not let the thermometer rest on the bottom of the glass (holding the thermometer lessens the likelihood of the thermometer tipping over the glass). If the thermometer is touching the bottom of the glass, it is also taking the temperature of the glass itself, although this would probably be a negligible reading. Make sure students understand that they should have the spot where the liquid stops rising at EYE LEVEL. 2. Distribute BLM 7.2.2, Taking and Recording Temperatures. Make sure the materials/substances are ready in advance. Prepare a chart of this blackline master and post it on the board. Review the procedures with students. Remind them to record their prediction before taking and recording the actual temperature of a substance or object. 3. Discuss student findings, and complete the board chart. The temperatures should fall within a narrow range. Ask students to explain why this occurs. 4. Students should be familiar with the range of temperature reasonably expected to occur in each of the following situations. Ask them to identify the temperature fluctuations (range) they would expect to see for: Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-4

11 Measuring Temperature Heat Subtask 2 Energy and Control An Integrated Unit for Grade 7 75 mins - outdoor temperatures; - indoor temperatures; - human body temperature; - cooking temperature; - pool temperature; - bath temperature. Distribute BLM 7.2.3, Matching Temperatures. Students may work alone or with a partner. The task is to identify the temperature range of each of the items in the Object column. (Answers are provided on BLM 7.2.4, Matching Temperatures - teacher copy). Discuss student findings. Ask students to discuss how accurate their predictions were. 5. Students should now have some everyday reference temperatures as they continue their study of heat. Adaptations Teachers are encouraged to: - involve the student in setting goals for work completion; - encourage risk taking; - provide varied opportunities for peer and/or group interactions (e.g., cooperative learning, sharing); - teach visual strategies for journal writing and/or note making (e.g., use of diagram/picture to represent content); - provide advance organizers to structure content (e.g., outlines, subtitles, paragraph frames); - encourage the use of lists, advance organizers, personal planner for personal organization; - allow opportunities for alternatives to writing (e.g., graphic representations, drama, media presentations, timelines, collages). Resources BLM BLM BLM BLM blm cwk blm cwk blm cwk blm cwk thermometers beakers/containers/pails sand ice lamps to heat water and sand Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-5

12 Measuring Temperature Heat Subtask 2 Energy and Control An Integrated Unit for Grade 7 Notes to Teacher Teacher Reflections 75 mins Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-6

13 Heat Capacity Heat Subtask 3 Energy and Control An Integrated Unit for Grade mins Description Students will investigate the difference between heat and temperature. They will compare the amount of heat in different volumes of a given liquid and in different masses of a given solid. By noting the rate of temperature change they will be able to make some generalizations about the heat capacity of common materials. Expectations 7s55 7s62 7s68 7s73 7s65 distinguish between the concept of temperature and the concept of heat (e.g., temperature is a measure of the average kinetic energy of the molecules in a substance; heat is thermal energy that is transferred from one substance to another); compare, in qualitative terms, the heat capacities of common materials (e.g., water and aluminum have greater heat capacities than sand and Pyrex); compile qualitative and quantitative data gathered through investigation in order to record and present results, using diagrams, flow charts, frequency tables, bar graphs, line graphs, and stem-and-leaf plots produced by hand or with a computer (e.g., plot a graph showing the decrease in temperature of various liquids from identical initial temperatures); identify different forms of energy that can be transformed into heat energy (e.g., mechanical, chemical, nuclear, or electrical energy); formulate questions about and identify needs and problems related to heat (e.g., interactions involving energy transfers), and explore possible answers and solutions (e.g., identify the steps that could be followed to test the effectiveness of the heating system in a home that uses solar energy); Groupings Students Working As A Whole Class Students Working In Pairs Students Working In Small Groups Teaching / Learning Strategies Demonstration Discussion Brainstorming Collaborative/cooperative Learning Experimenting Fair Test Assessment A Science and Technology Journal Assessment Rubric has been included as a blackline master in the Unit Wide Resources section (BLM 7.uw.5, Science and Technology Journal Assessment Rubric). Assessment Strategies Exhibition/demonstration Questions And Answers (oral) Learning Log Assessment Recording Devices Anecdotal Record Rubric Teaching / Learning Part A: Heat Capacity and Solids (40 minutes) Teacher Demonstration 1. Hold a piece of aluminum foil over a heat source using a pair of tongs. At the same time using tongs, hold a solid block of aluminum over the same heat source (Note: an aluminum pot may be substituted for the aluminum block). The two samples should be kept over the heat source (e.g., a flame) for about one minute. 2. While these two items are in the flame remind students that both are made from the same material. Have the students describe the difference between the materials (the foil is thinner than the block or pot, and has much less mass). Tell the students that both pieces of aluminum are at about C after one minute. 3. Ask students which piece of aluminum they believe will be hotter when removed from the flame. Have Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-7

14 Heat Capacity Heat Subtask 3 Energy and Control An Integrated Unit for Grade 7 them explain why they would make that choice. 200 mins 4. Remove the aluminum foil and wait about 20 to 30 seconds. Squeeze it between your index finger and thumb briefly. Note how hot it feels. Have a student come to the front to confirm your description (DO NOT HAVE THE STUDENT DO THIS FIRST!) You must ensure that the foil has cooled down to the point where it is merely warm. 5. Ask the students why you chose not to touch the block/pot first even though both the foil and the block were at the same temperature when they were first removed from the flame. Now remove the block/pot from the flame (DO NOT TOUCH THE BLOCK/POT!) Wait 20 to 30 seconds then immerse the block of aluminum, or aluminum pot in a pan of water or a nearby sink. Have the students observe what occurs. 6. Question: Why is the block/pot hotter than the foil, even though both consist of the same material? (Remember, both cooled for the same amount of time!) Through discussion lead students to the following conclusion: because the block/pot has a greater mass, it retains more heat than the aluminum foil, which loses its heat very quickly. In other words, the aluminum foil retains less heat because of its smaller mass. The small amount of heat in the foil dissipates quickly into the surrounding air through its relatively large surface area. 7. Reinforce the following concepts: - Heat is a form of energy. - All matter is made up of particles or molecules. - Heat refers to the total kinetic (energy of moving objects) energy of all the vibrating particles in a substance. It is the sum of the energy of all the particles. - Temperature is actually a measurement of the kinetic energy of the particles at the point in a substance, where the bulb of a thermometer is located. 8. Now that students have some knowledge of kinetic energy, ask them to provide a more detailed explanation of why the block had more heat than the foil. 9. Direct students to make a science journal entry to record what they learned in this lesson (L of the K.I.L.E. approach). Post the terms particles, molecules, and kinetic energy and encourage students to incorporate them into their entries. Remind them that labelled diagrams enhance journal entries, and are effective for review purposes. Part B: Heat Capacity of Water (40 minutes) This activity based on the I.N.S.I.T.E. method, is designed to show that a large volume of hot water contains much more heat than a small volume of water of the same temperature. Teachers should review the I.N.S.I.T.E. model with students. 1. Prior to the Lesson: Heat up water in several large containers and place them throughout the room. Groups of students should go to the nearest one to their desk. Place the containers on a hot plate on low heat to stabilize the temperature at about 70 0 C. Leave a thermometer in each container to show the temperature of the water. The thermometer should be suspended from a string or thermometer clamp so that the bulb of the thermometer is in the middle of the water. The hot water should be stirred occasionally to make the temperature uniform throughout. Have cool water available in large containers. Try to keep the water at a constant (cool) temperature - perhaps by packing some ice around the containers. (A good alternative is to use tap water, if the Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-8

15 Heat Capacity Heat Subtask 3 Energy and Control An Integrated Unit for Grade mins temperature of the tap water is below 20 0 C). Suspend a thermometer in the water. Use the same procedure you used for the hot water containers. 2. Distribute copies of The Amount of Heat in Hot Water (BLM 7.3.1). Review sections I., N., & S. and remind students they must state a hypothesis before beginning the investigation. In section I (Investigate) review the materials required, discuss the variables, and have the students record this information in the section provided. Read through the procedures and review sections T. and E. on page 2. Caution students to follow the appropriate safety procedures, then allow them to complete the investigation. 3. Follow-up: Review and discuss section E. (examine the results and write a conclusion). After discussing questions 1 to 4, encourage students to revise their responses to ensure they are correct. Part C: Heat Capacity of Various Substances (40 minutes) This activity, based on the I.N.S.I.T.E. method, is designed to allow students to compare the heat capacities of different substances. The students should work in groups numbers depending upon the number of materials available for this activity. 1. Prior to the Lesson: Heat up water to at least 70 0 C in several large containers, one for each group. Place several samples of materials with equal masses (as close as possible) in the same pail or container of hot water. For example, use a 50 g piece of each of the following: aluminum, copper, zinc, lead, rock, etc.) Give the samples time to reach a constant temperature between 70 0 C and C. Leave a thermometer in each container to get the temperature of the samples. There is no need to suspend the thermometer in water for this activity, however the water could be stirred. Use a stirring rod for this purpose. Have cool water available in containers as in the previous activity, or use tap water if it is below 20 0 C. 2. Divide the students into groups, and distribute copies of Heat Capacity (BLM 7.3.2). Review the blackline employed in Part A. Using the I.N.S.I.T.E. method: - Review and discuss I., N., & S. - Discuss I. (Investigate) to identify the materials required and to establish the variables for the investigation - Review T. and E. Note: Before beginning the investigation you may wish to let students predict which materials will have the highest heat capacities. Create a list, ranking the materials from highest to lowest according to heat capacity. 3. At the conclusion of the activity allow students to share their results. Discuss the questions in section E. (Investigate), then allow students time to revise their responses to ensure their information is accurate. In general, the students should be able to conclude that since the temperature of the water went up only slightly, and the temperature of the materials dropped significantly, water has a higher heat capacity (holds more heat) than any of the materials. In fact, water has the highest heat capacity of common materials. Make a chart of the heat capacities of common materials available to students so they can compare their results to the actual values. Part D: Rate of Temperature Change of a Liquid and Heat Capacity (40 minutes) In Part A, we examined the volume of a liquid and concluded that the larger the volume of liquid, the greater the heat capacity. In this experiment, students will learn that heat capacity can also be measured by the rate of temperature change in different volumes of liquid (water) heated to the same temperature. Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-9

16 Heat Capacity Heat Subtask 3 Energy and Control An Integrated Unit for Grade mins Prior to the Lesson: Review the safe use of a hot plate and hot water. If there are safety concerns, conduct this experiment as a group demonstration. 1. Following the instructions on Mass, Rate of Temperature Change and Heat Capacity (BLM 7.3.5), students will conduct an experiment to determine how the mass of a liquid affects the rate of temperature change, and how mass and rate of change affect heat capacity. 2. Distribute copies of BLM 7.3.3, Mass, Rate of Temperature Change and Heat Capacity to students. - Read the opening statement which describes the purpose of the investigation. - As a class identify the problem. Students should record a description of the problem in the space provided. - Read and briefly discuss section N. - Allow students to individually develop a hypothesis, which should be recorded in the space provided in section S. - Review the information in the remaining sections to ensure students know how to conduct the investigation. - Allow students to work in small groups to complete the investigation. 3. When the students have completed the investigation, have them share their results and present their conclusions. Generate class responses and have the students record these responses on their sheets in the appropriate place. It is essential that students understand the process one uses to develop conclusions, based on the results of an investigation, because they are required to complete the next investigation without assistance. 4. Teachers will evaluate this investigation using the Inquiry/I.N.S.I.T.E assessment rubric. Part E: Types of Liquids, Rate of Temperature Change, and Heat Capacity Students will investigate how the nature of a liquid affects the rate of temperature change, by investigating whether 100 g of water will take more or less time to reach a specific temperature than 100 g of glycerin, or liquid soap. Safety Note: Review the safe use of a hot plate and hot liquids. Students may conduct this investigation in small groups; however, if there are safety concerns, conduct the experiment as a teacher demonstration. 1. Read through Nature of a Liquid, Rate of Temperature Change and Heat Capacity (BLM 7.3.4) with the students. Generate a class response to "Identification of the Problem" and have the students record it on their blackline masters. Ask the students to individually develop and record a hypothesis. 2. Create four centres, one for each liquid. At each centre provide enough materials for two groups to perform the experiment. The two groups at each centre will test one liquid. The information for the other liquids will be gathered from the other groups and then shared as a whole class. 5. When the groups have finished their experiments, have the groups at each centre record their results on a chart displayed as an overhead or posted on the blackboard. If groups testing similar liquids get different results, try to ascertain which group had the most accurate data. Analysing the results achieved by other groups testing different liquids will help with this process. When reviewing the questions and conclusions in section E., generate class responses. Make sure the students record these responses on their sheets (they may wish to record them in a different colour). If you choose to evaluate this investigation, use the Inquiry/I.N.S.I.T.E rubric (see Unit-Wide Resources). Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-10

17 Heat Capacity Heat Subtask 3 Energy and Control An Integrated Unit for Grade mins Adaptations Teachers are encouraged to: - involve the student in setting goals for work completion; - encourage risk taking; - provide varied opportunities for peer and/or group interactions (e.g., cooperative learning, sharing); - teach visual strategies for journal writing and/or note making (e.g., use of diagram/picture to represent content); - provide advance organizers to structure content (e.g., outlines, subtitles, paragraph frames); - encourage the use of lists, advance organizers, personal planner for personal organization; - allow opportunities for alternatives to writing (e.g., graphic representations, drama, media presentations, timelines, collages). Resources BLM BLM BLM BLM blm cwk blm cwk blm cwk blm cwk wooden stir sticks aluminum foil tongs an aluminum block or pot containers/pails thermometers thermometer clamp 50g (or equal mass) of various metals 100g of glycerin or liquid soap safety glasses stirring rod beakers expanded polystyrene cups hot plates retort stands Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-11

18 Heat Capacity Heat Subtask 3 Energy and Control An Integrated Unit for Grade 7 balance scale 200 mins Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-12

19 Heat Capacity Heat Subtask 3 Energy and Control An Integrated Unit for Grade 7 Notes to Teacher Part A Notes 200 mins In step 1, heat the foil and the block long enough to create approximately the same temperature in both. If the foil melts, take it out of the heat and then return it to the heat. Keep the block in the heat the whole time but stop if it starts to melt. If you use a Bunsen burner both materials will reach the required temperature in about two minutes. Place the burner on a stand so it is easy for the students to see what is happening. A hot plate may also be used provided students can see what is happening from where they are positioned. The flame of a burner gives a better indication of heating because the students can see the flame which they know is hot. There is no indication of heat from the hot plate. 2. Do not be too concerned about the actual temperature of the pieces. The important thing is that the two have about the same temperature just before they are removed from the heat. Part B Notes 1. Use 3-4 L of water in the large containers. It is easier to maintain a more constant temperature in a large volume of water which means each group will be using hot water which is about the same temperature. If the thermometer is touching the bottom of the beaker it will probably produce a higher reading. Make sure the thermometer is suspended or clamped with its bulb immersed in the middle of the water. 2. a) Try to keep the hot water at a stable temperature by placing it on a hot plate at a specific setting. Note what the setting is when the temperature is steady and put tape over the dial so that no one changes the dial setting. b) If using tap water to get cool water, run the water until a stable temperature is reached, preferably below 20 degrees C. c) Steps a) and b) will help to minimize the number of variables in the experiment. 3. You may want to assist students when they transfer hot water and ensure that they use tongs to hold the hot water beaker. Have a route set out for them to use when walking to each station to avoid hot water traffic jams. 4. Students will get best results if they get a big temperature change after adding the hot water to the cold water. For example, if the temperature of the mixture is only a degree or two warmer than the cool water, the results will not be convincing. Make the hot water a lot hotter than the cool water, but avoid extremely hot water for safety reasons. 5. Students should try to explain the difference in the final temperatures by understanding which transferred the most heat to the mixture, the 40 ml or the 80 ml of hot water. Referring back to the previous activity may help explain the temperature change after mixing. The 80 ml of hot water, which had a greater mass, had more heat because it had more vibrating particles. Therefore, when mixed with the cool water it transferred more heat to the cool water, than the 40 ml sample. As a result, the temperature change is greater when a larger amount of hot water is added. Part C Notes In general, heat capacity is the ability of a substance to hold heat. Since we cannot directly measure the amount of heat in a hot piece of copper, for example, we can measure the amount of heat it transfers to a cup of cool water by noting the change in temperature when it is added to the water. Although students will Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-13

20 Heat Capacity Heat Subtask 3 Energy and Control An Integrated Unit for Grade mins be measuring the relative heat capacity of materials and not the actual heat capacity, it is good for them to be aware of what heat capacity is in terms of energy. If you heat water using a kettle, it takes about 4200 J of energy to raise the temperature of 1 g of water by 1 degree C. To raise the temperature of 1 g of lead by 1 degree C requires only 130 J of energy. This amount of energy, 4200 J for water and 130 J for lead is a measure of the heat capacity of the substance. Similarly, if warm lead is added to cool water, 1 g of the lead will release 130 J of heat to the cool water for every degree the lead drops in temperature. If 1 g of lead drops from 70 degrees C to 69 degrees C it will release 130 J. If 1 g of lead drops from 70 degrees C to 60 degrees C it will release 10 x 130 J or 1300 J of energy. From the chart of heat capacities you can determine which materials hold the most heat, and therefore, which transfer the most heat when added to the water.. Since water has one of the highest heat capacities compared with other materials, water: a) holds more heat and therefore cools down more slowly; b) transfers more heat; c) takes more heat to raise its temperature and therefore heats up more slowly (another way of looking at it is that water will absorb more heat than other materials before its temperature goes up by 1 degree C). 1. In the large container use a large volume of hot water so the temperature will stay constant and not change much when the samples are returned. Boiling water (100 degrees C) will maintain a good constant temperature. Note: Review safety procedures before the students work with boiling water. 2. Students should add just enough cool water to the expanded polystyrene cup to completely submerge the sample. This will cause a bigger change in the water temperature when the hot sample is added. Try to get samples that are fairly large, but still small enough to be completely submerged. Reduce the amount of cool water in the cup if the water does not change temperature enough. Try 50 ml of cool water first. If that is not enough to cover the biggest sample try a larger amount of water. 3. If the samples are compact, cubes, spheres, or rectangular blocks with similar dimensions, the results will be better because less cool water will be needed to completely cover them in the cups. Avoid very large samples. The volume of a standard expanded polystyrene cup is about 200 ml so the total volume of the cool water and sample must be less than 200 ml. 4. Try to select samples with noticeably different heat capacities. (A heat capacity chart in a textbook is a useful reference). 5. To make it easy to find each specific sample in the large beaker of hot water, put labels around the bottom of the large container to show where each is located. Remind students to place each sample next to the label, when they are through using it. 6. When the students have completed the activity, they should be able to compare the heat capacity of the water and the samples by making a temperature scale showing the initial temperature of a sample, the initial temperature of the water, and final temperature of the mixture. Note the small temperature change for the water and the big change for the sample. This shows that water has a much higher heat capacity than the sample, because it can absorb a lot of heat while only rising in temperature a few degrees. Once the students understand this concept, record the final temperature of the other samples on the scale, and compare each to the temperature of the water. 100 o C<-- initial temperature of the sample 90 o C 80 o C 70 o C Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-14

21 Heat Capacity Heat Subtask 3 Energy and Control An Integrated Unit for Grade 7 60 o C 50 o C 40 o C <-- final temperature of the water plus sample 30 o C 20 o C <-- initial temperature of the water 200 mins Remember the water temperature went up slightly but the temperature of the samples dropped a lot. Therefore, water has a higher capacity (holds more heat) than any of the samples. Water has the highest heat capacity of common materials. Make a chart of heat capacities available for students to compare their values with the actual values listed on the chart. Sample specific heat capacities water 4200 J/kg/ C aluminum 900 J/kg/ C "When a sample is added to cool water, the higher the rock 880 J/kg/ C heat capacity of the sample, the greater the increase iron 460 J/kg/ C in the temperature of the cool water." copper 390 J/kg/ C lead 130 J/kg/ C Part D Notes 1. If space or the availability of equipment are concerns, have students work in small groups, or use a teacher demonstration. 2. If using small groups, students should be aware of the safety aspects, including the wearing of goggles at all times. If glycerin or oil are spilled on the skin, wash them off with soap and water. Refer to BLM 7.1.1, Saftey Contract for safety guidelines. 3. Prerequsites: Students should be able to: - construct charts for recording data; - read a thermometer accurately; - assemble a retort stand and clamp; Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-15

22 States of Matter and the Particle Theory Heat Subtask 4 Energy and Control An Integrated Unit for Grade mins Description Students will examine the three states of matter and will compare the motion of particles in a solid, liquid, and a gas using the particle theory. Expectations 7s56 7s61 7s69 compare the motions of particles in a solid, a liquid, and a gas using the particle theory; describe the effect of heat on the motion of particles and explain how changes of state occur (e.g., from a liquid into a gas or vapour); communicate the procedures and results of investigations for specific purposes and to specific audiences, using media works, written notes and descriptions, charts, graphs, drawings, and oral presentations (e.g., use a diagram to illustrate convection in a liquid or a gas). Groupings Students Working As A Whole Class Students Working In Small Groups Teaching / Learning Strategies Demonstration Experimenting Concept Clarification Model Making Assessment A Science and Technology Journal Assessment Rubric has been included as a blackline master in the Unit Wide Resources section (BLM 7.uw.5, Science and Technology Journal Assessment Rubric). Assessment Strategies Exhibition/demonstration Learning Log Questions And Answers (oral) Assessment Recording Devices Anecdotal Record Rubric Teaching / Learning Part A: The Particle Theory (30 minutes) 1. Distribute blackline master Particles and States of Matter (BLM 7.4.1). Pose the question, "What is all matter composed of?" Most students in grade 7 will be aware that all things are composed of particles called atoms (many will even know the structure of atoms) and molecules. Review the structure of a water molecule (H20) to reinforce their understanding of the structure of matter. 2. Identify the three states of matter ('solid', 'liquid', and 'gas'). Use water, ice and water vapour as examples. Ask the following question: If water is made up of the same molecule why are there three different states of matter? Have the students speculate about the states of matter and their relationship to the amount of heat that the matter contains. 3. Pose the question, What is the impact of the heating or cooling the water (liquid)? Students should be able to explain that cooling water eventually causes it to change to ice at a specific temperature and heating water eventually turns it to vapour. 4. Use blackline master BLM 7.4.1, Particles and States of Matter to explain the relative position of Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-16

23 States of Matter and the Particle Theory Heat Subtask 4 Energy and Control An Integrated Unit for Grade mins molecules in the three states of the H20 molecule. Start with the liquid state. Explain that when heat is applied, the particles of matter spread apart and become more "random" in their pattern. Conversely, when heat is removed, the particles move closer together and develop a more regular pattern. This causes a change in the state of the matter. Examine the diagrams. The particles are closest together in the solid state (this occurs at zero degrees Celsius). In the liquid state the particles are further apart. In the gaseous state, the particles are spread apart and many mix with the air around them. Note: Vapourization does not begin at 100 degrees Celsius. Vapourization (or evaporation) is continually taking place when the temperature of water is above zero degrees Celsius. The greater the application of heat the higher the rate of evaporation. 5. Have the student make a science and technology journal entry about what they learned in this lesson. Part B: Volume of Liquid (30 minutes) 1. Review the following with students. Temperature is a way of measuring the average energy of particles in an object. A thermometer is an instrument used to measure temperature. The students will be using thermometers that contain a liquid. Talk about the structure of the thermometers. There is a bulb at the bottom containing a "reservoir" of the liquid (using alcohol). When the temperature of the liquid increases, the liquid moves up the tube of the thermometer (higher on the scale). Pose the question to the class, Why does the liquid rise and fall? Tell the students they will study how heat affects the liquid in a thermometer to determine how heat affects all liquids. 2. Hand out the blackline master, Changes in the Volume of a Liquid (BLM 7.4.2). Ask students to predict what a thermometer will read when it is immersed in a beaker containing: tap water, ice water, and hot water. Predicting exact temperatures is not necessary. An estimate or range is all that is required at the hypothesis stage. 3. Have the students work on their experiments. When they are through, reconvene and as a class generate a conclusion. As in previous experiments, the students should record the class results in a different colour. Collect the sheet for evaluation (use the Inquiry/I.N.S.I.T.E. assessment rubric). Part C: Volume of a Solid (30 minutes) Conduct this as a teacher demonstration. 1. Prepare and store in separate containers, 1L of ice water, and 1L of hot water. 2. Show the ball and ring apparatus to the students. 3. Distribute blackline master, Changes in The Volume of a Solid (BLM 7.4.3). Have students read the Narrow the Problem section. Have students complete the State the Hypothesis section. 4. Before conducting the experiment draw the students' attention to Observations 1, 2, and 3 in section E., so they are prepared to record information. 5. Following the demonstration, allow time for students to develop and write a conclusion. Remind students to use correct scientific terminology when recording observations, and writing conclusions. 6. When they are through, reconvene the class and as a group develop a conclusion. As in previous experiments, the students record the 'correct' answers and conclusions on their sheets (they may wish to use a different colour to record this information). Collect the sheets for assessment (Use the Inquiry/I.N.S.I.T.E. assessment rubric for this purpose). Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-17

24 States of Matter and the Particle Theory Heat Subtask 4 Energy and Control An Integrated Unit for Grade mins Note: If you experience problems performing this demonstration, immerse either the ball or the ring in VERY hot water and at the same time, immerse the other one (ball or ring) in VERY cold ice water. This may help improve the results for demonstration purposes. Part D: Volume of a Gas (30 minutes) Conduct this investigation as a teacher demonstration. 1. Review what has been learned in the previous two experiments about the effects of heating and cooling liquids and solids. 2. Distribute the blackline master, Changes in the Volume of a Gas (BLM 7.4.4). Have students compile the "Identify the Problem" section. They may refer to the two previous investigations if they experience difficulty. 3. Ensure that students are familiar with the requirements of section E., then conduct the experiment following the procedures outlined on BLM 7.4.4, Changes in the Volume of a Gas. 4. Following the teacher demonstration, give the students time to develop a conclusion. Remind the students to use correct scientific terminology. 5. When they are through writing their conclusions, reconvene the class and as a group develop a conclusion. As in previous experiments, the students should record this information in a different colour. The teacher may wish to collect the sheets for assessment. (Use the Inquiry/I.N.S.I.T.E. assessment rubric for this purpose). Part E: The Particle Theory (30 minutes) 1. Reinforce the concept of relative position using the following explanation: Molecules are in constant motion in all matter, above absolute "zero" (see BLM 7.2.1, The Measurement of Heat, subtask 2). However, if a "snapshot" is taken, we can observe the position of the molecules (distance apart and pattern) at one point in time. This is what is termed relative position. Think of taking a snapshot of someone juggling tennis balls. Although the balls are moving when the snapshot is taken, they are 'frozen' in the snapshot so we can easily observe their position (distance apart and pattern). 2. Hand out the blackline master, The Particle Theory (BLM 7.4.5). Read through the experiment and have the students complete part S. - "State the Hypothesis". 3. Have the students work in small groups (of 3 or 4) to complete the experiment. When they are through, reconvene the class and as a group develop a conclusion. As in previous experiments, develop class answers which students should record on their sheets (use a different colour). Collect the sheets for assessment. (Use the Inquiry/I.N.S.I.T.E. assessment rubric for this purpose). Part F: The Kinetic Molecular Theory (30 minutes) 1. In previous experiments, students learned that the volumes of solids, liquids and gases increases when heat is applied. They also learned that the distance between particles in these substances increases when heat is applied. Students will now identify how the particles "moved away" from each other, with the application of heat. 2. Review the conclusions developed in the two previous investigations (Changes in the Volume of a Gas - BLM and The Particle Theory - BLM 7.4.5). Students should be aware that particles move farther Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-18

25 States of Matter and the Particle Theory Heat Subtask 4 Energy and Control An Integrated Unit for Grade 7 apart when heat is applied. 3. Discuss the question: "How and why do these particles move apart?" 180 mins 4. Begin a discussion of Kinetic Molecular Theory. Students should be able to state that it is the distance between molecules (particles) which accounts for the differences in three states of matter (liquid, solid, gas) with the same molecule. Molecules are in constant motion in all matter above "Absolute Zero". The students may not have been introduced to the concept of absolute zero in a previous subtask. Absolute zero (-273 o C) is the temperature at which the molecules of a substance cease to be in motion. The temperature of an object determines how fast the atoms and molecules which make up an object shake, or oscillate. As an object is cooled, the oscillations of its atoms and molecules slow down. For example, as water cools, the slowing oscillations of the molecules allow the water to freeze into ice. In all materials, a point is eventually reached when all oscillations are the slowest they can possibly be. The temperature which corresponds to this point is called absolute zero. Note that the oscillations never come to a complete stop, even at absolute zero. Conversely, as an object is heated, the oscillations of its atoms and molecules speed up. As this happens, particles begin to collide with each other, causing them to move a greater distance from each other. The greater the number of collisions, the greater the distance between the particles. When the particles collide, energy is released as heat, or is converted to the motion of another particle. The energy from motion is called kinetic energy. The amount of kinetic energy an object has is related to the speed (velocity) of the particles and the mass of the particles. When heat energy is applied to an object the particles move faster (heat to kinetic transfer). As the particles move faster, they collide with each other. When they collide, some energy is released as heat, and the rest of the energy is transferred to the next molecule which in turn moves, and so on. Again, remind the students that the greater the heat of an object, the faster its particles are moving and colliding. Using water as a reference, illustrate the Kinetic Molecular Theory using the blackline master, The Kinetic Molecular Theory (BLM 7.4.6). Adaptations Teachers are encouraged to: - involve the student in setting goals for work completion; - encourage risk taking; - provide varied opportunities for peer and/or group interactions (e.g., cooperative learning, sharing); - teach visual strategies for journal writing and/or note making (e.g., use of diagram/picture to represent content); - provide advance organizers to structure content (e.g., outlines, subtitles, paragraph frames); - encourage the use of lists, advance organizers, personal planner for personal organization; - allow opportunities for alternatives to writing (e.g., graphic representations, drama, media presentations, timelines, collages). Resources BLM blm cwk Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-19

26 States of Matter and the Particle Theory Heat Subtask 4 Energy and Control An Integrated Unit for Grade 7 BLM blm cwk 180 mins BLM BLM BLM BLM blm cwk blm cwk blm cwk blm cwk drink crystals dish cloth beakers thermometers stop watches pails/large containers hot plates ball retort stand with ring apparatus 2 L pop bottles or Erlenmeyer flask small, non-latex spherical balloons ice elastics oven mitts heat resistant mats petrie dishes Notes to Teacher Teacher Reflections Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-20

27 Heat Transfer Heat Subtask 5 Energy and Control An Integrated Unit for Grade mins Description In the previous subtasks students were introduced to the Kinetic Molecular Theory and the fact that when substances are heated, the particles in the substances speed up and begin to collide. In this subtask, students expand this understanding by examining how heat is transferred within a substance. Note: All matter (solid, liquid and gas) has some level of conductivity, however, solids are better conductors than liquids or gases so only solids will be used in the experiments in this subtask. Expectations 7s57 7s58 7s64 7s69 7s65 7s67 7s66 explain how heat is transmitted by conduction, convection, and radiation in solids, liquids, and gases (e.g., conduction: a pot heating on a stove; convection: a liquid heating in the pot; radiation: the air being warmed by heat from the element); describe how various surfaces absorb radiant heat; design and build a device that minimizes energy transfer (e.g., an incubator, a Thermos flask). communicate the procedures and results of investigations for specific purposes and to specific audiences, using media works, written notes and descriptions, charts, graphs, drawings, and oral presentations (e.g., use a diagram to illustrate convection in a liquid or a gas). formulate questions about and identify needs and problems related to heat (e.g., interactions involving energy transfers), and explore possible answers and solutions (e.g., identify the steps that could be followed to test the effectiveness of the heating system in a home that uses solar energy); use appropriate vocabulary, including correct science and technology terminology, to communicate ideas, procedures, and results (e.g., state the boiling and freezing points of water, room temperature, and body temperature in degrees Celsius; correctly use the terms heat conductor and heat insulator); plan investigations for some of these answers and solutions, identifying variables that need to be held constant to ensure a fair test and identifying criteria for assessing solutions; Groupings Students Working As A Whole Class Students Working In Pairs Students Working In Small Groups Teaching / Learning Strategies Demonstration Direct Teaching Experimenting Fair Test Note-making Problem-solving Strategies Assessment Assessment Strategies Exhibition/demonstration Performance Task Questions And Answers (oral) Assessment Recording Devices Anecdotal Record Rating Scale Rubric Teaching / Learning The Transmission of Heat By Conduction, Convection and Radiation Background Information: Review the particle theory. All particles in any substance are moving at different rates depending on how hot they are. The hotter the substance, the faster the particles move. 1. The vibrating particles are "attracted" to each other which keeps the substances together. Question: What would happen if there was no attraction between particles? Answer: There would be no matter. The particles would float around randomly never collecting to create matter. Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-21

28 Heat Transfer Heat Subtask 5 Energy and Control An Integrated Unit for Grade mins 2. When vibrating particles come in contact with particles that are vibrating at a slower rate, the faster vibrating particles cause the slower particles to vibrate faster but not necessarily at the same rate as the faster particles. This creates a "domino effect". Faster particles continue to come into contact with slower particles which then vibrate faster, and so on. Heat is also transferred from particle to particle in this process. Heat can also be transferred from one substance to another, by conduction, convection and radiation. The following investigations will help students understand these three concepts. Part A: Conduction (60 minutes) 1. Introduce conduction by reviewing the concepts of heat capacity and the Kinetic Molecular Theory. The students should know that different materials "hold" different amounts of heat, and that heat is transferred among particles as they vibrate and collide. They have not examined the rate of heat transfer within different materials. 2. Hold up a spoon. Question: If we apply heat to the head (round part) on the spoon, what happens to the particles on the other end? The students should be able to explain that the particles will vibrate faster and begin to collide with other particles causing a chain reaction which moves the heat along the spoon away from the heat source. 3. The heat will move a greater distance from the heat source if more heat energy is applied. You may wish to use the following demonstration to help students understand this concept. - Use some toy car tracks to make a ramp taping one end to a high area, such as a desktop and the other to a lower area such as the floor. - Place several cars at the bottom of the ramp. Space the cars about 2 cm to 5 cm apart. - When the car strikes the cars at the bottom of the ramp it will cause a chain reaction. (In the "first" run, make sure the last cars do not move. Do several tests before the demonstration so you know how to space the cars to get this result).the kinetic energy of the car is transferred to the other cars, in the same way that heat energy is transferred when one particle collides with another. - Increase the angle of the ramp so the velocity of the car is greater. - Release the car again (this time it should move all the cars at the bottom of the ramp). The car has more kinetic energy, so enough energy is transferred from car to car to cause all the cars to move. The same thing happens when more heat energy is applied to the spoon. Particles a greater distance from the heat source are affected as more heat energy is applied so the heat moves further down the spoon. The transfer of heat energy through a material is called "conduction". 4. Question: "Do all materials "conduct" heat at the same rate?" Tell the students that the next teacher demonstration will examine this question. 5. Place a pot of water on a heat source (i.e., hot plate). Have a variety of spoons of different types (metal, wood, plastic, etc.) available beside the pot. 6. Ask the students which spoon they would choose to stir the hot water in the pot. - Have a student select a spoon and place that spoon in the pot. Ask the student to explain why they chose that spoon. Leave the spoon in the water. Ask another student to select a spoon and place it in the pot. Repeat this process until all the spoons have been chosen. 7. Ask the students to predict which spoon will be the hottest. Make sure students explain their predictions. In the ensuing discussion lead students to conclude that metals are better conductors of heat. In the next Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-22

29 Heat Transfer Heat Subtask 5 Energy and Control An Integrated Unit for Grade mins activity, students are asked to design and conduct an experiment which compares the rate at which different metals conduct heat. 8. Before beginning the experiment complete Conducting an Experiment and Variables (BLM 7.5.1) with students. A teacher answer sheet BLM 7.5.2, Conducting an Experiment and Variables - Teacher Answers has been provided. 9. Distribute copies of Metal Conductors BLM to students. Divide the students into small groups. Using the I.N.S.I.T.E. method students will design and conduct an experiment which demonstrates the rate at which different metals conduct heat (students should be very familiar with the I.N.S.I.T.E. method). They must complete BLM 7.5.3, Metal Conductors, and submit it at the end of the investigation for evaluation. NOTE: Students will require at least 3 different metals for this experiment. Part B: Convection (30 minutes) Convection only occurs in fluids (liquid and gas). Both will be used in the following activities. BEAKER OF WATER WITH CIRCULATING SUBSTANCE - teacher demonstration 1. Place a beaker of water on a hot plate. Bring the water to a boil and have students describe what they see (bubbles, steam, etc.) 2. Tell the students you are going to add sawdust (or confetti) to the water. Ask them to predict how the sawdust will travel in the water and have them illustrate their prediction on the board. 3. Add the sawdust to the boiling water (the sawdust will rise to the top of the water, travel across the water's surface, fall down the opposite side of the beaker, then travel across the bottom of the beaker and up the opposite side). Draw a diagram on the board to illustrate the movement of the sawdust (confetti). A 'current' has been created in the boiling water. 4. Identify examples of currents in the environment that demonstrate the same principle (ocean currents, air currents, etc.) 5. Tell students that we can explain what is happening in the beaker by recalling what they learned about the transfer of heat. Heat from the hot plate is conducted through the glass beaker. This causes the particles of water at the bottom of the beaker to vibrate at a faster rate. As the water heats up, the water particles at the bottom move further apart and become less dense. Because it is less dense, the water begins to rise creating an upward current. The particles cool as they rise to the top. When they reach the top they are pushed to the side by other rising particles. The cooler particles begin to fall. When they reach the bottom they are reheated, and once again begin to rise. Refer to the diagram on the board. Label the particles as being hotter (having more kinetic energy) or cooler (having less kinetic energy). Label the relative density of the areas of water in the diagram as well. Tell the students that this kind of heat transfer or movement of heat is called "Convection". 6. Have the students write a science and technology journal entry describing what they learned in this lesson (L. of the K.I.L.E. approach). Evaluate using The Journal Rubric (BLM 7.UW.5, Science and Technology Journal Assessment Rubric). Post the terms convection, particles/molecules, density, current and kinetic energy and encourage students to use them in their entries. Remind students to include labelled diagrams. SPINNING SPIRAL (30 minutes) 7. Ask students whether convection can occur in a solid. Answer: No. Molecules are strongly bonded Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-23

30 Heat Transfer Heat Subtask 5 Energy and Control An Integrated Unit for Grade 7 together. Can this happen in a gas? 270 mins 8. Use a demonstration to illustrate how air circulates. Cut a piece of paper into a spiral (see BLM 7.5.4, Spiral Template for a template) and attach a piece of string to one end of the spiral. 9. Holding the string, suspend the spiral over the boiling water (the paper spiral should begin to spin because of the air current above the water). 10. Ask the students if they can use their understanding of convection in liquids to explain why the spiral is spinning. They should be able to provide the following explanation. As the water boils and the water vapour rises, the particles in the air above the heat source gain kinetic energy and heat. As they vibrate faster and move further apart they become less dense and begin to rise creating an upward air current. As the hot air continues to rise the air (particles) begin to cool and fall. They are replaced by other rising particles and so a current is created. Currents are created in air, through convection in the same way that currents are created in liquids. 11. Discuss the following to give students a practical example of convection. During the day the land is heated by the sun. Radiant heat from the land heats the air which becomes less dense and begins to rise. However, water (oceans, lakes) does not heat up as quickly, so the air above these bodies of water is cooler than the air on the adjacent land. The cooler air over the water, moves over the land to replace the rising warm air. As it rises, it begins to cool as it comes into contact with the cooler air higher in the atmosphere. As air cools its density increases and it begins to fall. When it falls, it moves over the water to replace the cooler air which is continually moving from the water to the land. Simply, as warm air rises, or moves to cooler areas, it leaves behind a "low pressure zone". Cooler air moves into the low pressure zone to replace the warm air. This movement of air creates the convection currents we recognize as wind. 12. Hand out blackline master Convection Questions (BLM 7.5.5). Have the students answer the questions on their own. Review the answers and allow time for corrections. The answers are provided as Convection Questions - Teacher Answers (BLM 7.5.6). 13. Follow-up: Provide students with newspaper weather maps showing high and low pressure areas. You could also discuss a weather broadcast. Use the maps to further discuss convection. 14. Following the discussion, have the students draw a diagram to illustrate the movement of air. The diagram should include a body of water, a land mass, and sky (clouds). Coloured arrows should be used to indicate the movement of air. On the back of their illustration they should include a written explanation which explains how air moves (convection) and how this movement of air creates our weather patterns. PART C: Radiation (30 minutes) Radiation occurs when heat is absorbed and given off. In the demonstration use a strong heat source to achieve the best results (see Teacher Notes). Activity A (teacher demonstration) How a Radiometer Works: Teacher Notes The blackened side of a radiometer absorbs more heat than the white side. Radiant energy heats up a small number of molecules on the surface of the darkened side of the vanes. The remaining air molecules in the bulb are driven away by the more energetic molecules close to the darkened surface, causing the vanes to rotate. Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-24

31 Heat Transfer Heat Subtask 5 Energy and Control An Integrated Unit for Grade mins 1. Explain to the students that the instrument consists of four vanes, each of which is darkened on one side and white on the other. The inside of the bulb is a partial vacuum. 2. Place the radiometer on a flat surface (e.g., desk in the centre of the class so that all students can see). 3. Place a heat source (lights, etc.) approximately 30 cm from the instrument. 4. Have the students predict what will happen when heat is applied to the radiometer; then turn on the light (the vanes begin to spin). Note the direction of the spin. Ask the students to explain what is happening. 5. Although the students may have some experience with light and colour, a quick review of the concept of light absorption is beneficial at this point. Discuss what happens to dark and light objects on sunny days. (Light is a form of energy. When it hits objects it can be reflected (bounced away) or absorbed. Darker objects absorb light energy and convert it to kinetic molecular energy and heat.) How does this explain what happens in the radiometer? See if students can provide the following explanation: The dark sides of the vanes absorb more heat and have more kinetic energy than the light sides. This greater kinetic energy (faster moving particles on the darkside) creates the "push" which moves the vanes. Ask the students to explain how the vacuum in the bulb helps the movement of the vanes. Simply, there is not air (gas molecules) so there is no resistance. The vanes move freely, because there is nothing to slow or stop their motion). 6. Using Heat Radiation (BLM 7.5.7) students will work through an experiment to determine how surface colour affects the amount of radiant energy absorbed by a material. 7. The Inquiry/I.N.S.I.T.E. assessment rubric should be used to evaluate this experiment. Part D: Heat Transfer in Everyday Life (30 minutes) 1. In previous activities students learned how heat energy is transferred. Using the blackline master, Heat Transfer in Everyday Life (BLM 7.5.8) the students work in small groups to identify examples of heat transfer. Part E: The Frozen Ice Treat Box - Build It (40 minutes) 1. Distribute the Frozen Ice Treat Box Challenge (BLM 7.5.9) and review the following situation with the students. You are planning to go on a class trip to the beach as part of the unit on HEAT. As your class leaves the school the teacher will give each student a frozen ice treat. You must build an insulated container which will keep the frozen ice treat as cold as possible for as long as possible during the trip. The container must be designed so it is easy to get the frozen ice treat in and out of the insulated container. 2. Make it clear to the students that what is being measured and evaluated in this activity is the container's ability to maintain a temperature without a transfer of heat. Remind students to not waste time and energy by making their container look pretty. 3. Divide the class into eight groups. Each group will use a different type of insulating material to build an insulated container. Discuss the concept of a "fair test" with the students and the importance of controlling variables. 4. Distribute materials to each group. See the "materials" section of BLM 7.5.9, The Frozen Ice Treat Box Challenge. Ensure that the tissue boxes used in this experiment are all the same size. Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-25

32 Heat Transfer Heat Subtask 5 Energy and Control An Integrated Unit for Grade mins 5. Have the groups follow the "procedure" on BLM 7.5.9, The Frozen Ice Treat Box Challenge to build their frozen ice treat box. Remind the students to use the materials efficiently. 6. Distribute a frozen ice treat to each group (you will probably want a box of frozen ice treats so that you can give each student a frozen ice treat at the conclusion of this activity). Have the students measure the temperature of both the frozen ice treat and the interior of their insulated container. If possible give each group two thermometers to do their measuring. If this is not possible remind the students to wait for the thermometers to return to "normal" temperature between measurements. 7. Have each group place the frozen ice treat in their insulated container. Record the initial temperature of the inside of the insulated container and the frozen ice treat on the chart on BLM , Frozen Ice Treat Box Challenge Temperatures. Students should leave the container untouched for an hour. Part F: The Frozen Ice Treat Box - Test It (40 minutes) 1. After the frozen ice treat has been in the insulated container for an hour have each group remove the frozen ice treat and measure the temperature of the frozen ice treat and the interior of the insulated container. Record the temperature of the frozen ice treat and the interior of the insulated container using the chart on BLM , Frozen Ice Treat Box Challenge Temperatures. 2. Have the students open their frozen ice treat and use a measuring cup to measure the amount of liquid that melted. Record the information on BLM , Frozen Ice Treat Box Challenge Temperatures. 3. Have each group create three line graphs. Two graphs should illustrate the temperature changes in the frozen ice treat and the container. The third graph should illustrate the amount of liquid which accumulates as a result of the melting. This is a great opportunity to incorporate spreadsheets and computer generated graphs in the curriculum. 4. Use chart paper to create a class chart. Record all results so the effectiveness of the different types of insulation can be compared. Create a second chart which ranks the insulation materials tested (in order from best to worst). Post these charts in the classroom for use during the culminating task. 5. Discuss the results of this experiment. Include in the discussion how materials affect heat transfer, the effectiveness of different materials as insulators, why some materials are better insulators than others, the characteristics of materials that are good insulators (good insulation materials allow for pockets of air within the structure of the material itself, and since air is a poor conductor of heat it makes the material a good insulator), and the effect of combining different materials in the creation of insulated containers. Adaptations Teachers are encouraged to: - involve the student in setting goals for work completion; - encourage risk taking; - provide varied opportunities for peer and/or group interactions (e.g., cooperative learning, sharing); - teach visual strategies for journal writing and/or note making (e.g., use of diagram/picture to represent content); - provide advance organizers to structure content (e.g., outlines, subtitles, paragraph frames); - encourage the use of lists, advance organizers, personal planner for personal organization; - allow opportunities for alternatives to writing (e.g., graphic representations, drama, media presentations, timelines, collages). Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-26

33 Heat Transfer Heat Subtask 5 Energy and Control An Integrated Unit for Grade 7 Resources BLM blm cwk 270 mins BLM BLM BLM BLM BLM BLM BLM BLM BLM blm cwk blm cwk blm cwk blm cwk blm cwk blm cwk blm cwk blm cwk blm cwk tissue boxes masking tape corrugated cardboard paper (for crumpling) aluminum foil plastic bubble wrap cotton balls (large) extruded polystyrene (approx 1.5 cm thick) cotton garment (clean old T-shirt or socks) wool garment (clean old sweater or socks) sawdust or confetti frozen ice treats toy cars (optional activity) toy car tracks (optional activity) spoons (metal/wood/plastic) Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-27

34 Heat Transfer Heat Subtask 5 Energy and Control An Integrated Unit for Grade 7 hot plate radiometer thermometers felt of 4 different colours lamps candle (optional light source) retort stand with clamp beakers 270 mins Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-28

35 Heat Transfer Heat Subtask 5 Energy and Control An Integrated Unit for Grade 7 Notes to Teacher CONDUCTION 270 mins Conduction is the transfer of heat between substances that are touching and are at different temperatures. Usually, heat transfer by conduction occurs at a faster rate in solids than in liquids or gases. All types of substances conduct heat; however, they do not all do so equally well. Vibrating particles release kinetic energy. When a warm substance touches a cold substance, the collision of their particles results in a gain of kinetic energy by the particles in the colder substance and a loss of kinetic energy by the particles in the hotter substance. The transfer of kinetic energy from hot to cold is the transfer of heat from hot to cold. The amount of heat transferred depends on the ability of the substance to conduct heat energy. The ability to conduct heat is called CONDUCTIVITY. The kind and size of a substance affect the speed at which heat is conducted. A substance that transfers heat easily is called a CONDUCTOR. Some examples are copper, iron, aluminum, lead and brass. A substance that does NOT transfer heat easily is called an INSULATOR. Some examples are plastic, rubber and wood. CONVECTION Convection is the transfer of heat by the movement of a fluid (LIQUID OR GAS) from an area with a high temperature to an area with a low temperature. Convection never occurs in solids. When fluids are heated, particles expand and become less dense so they rise. When the particles rise, they are constantly vibrating and colliding with the particles of cooler fluids so they lose some of their kinetic energy and cool themselves. And as a result, they become more dense and fall. This whole process creates a continuous rising and falling of fluids which is referred to as a CONVECTION CURRENT. A good example is a pond. The surface water cools in the autumn and the cool water falls. It is then warmed by the water closer to the bottom of the pond so it rises again creating a convection current. This current is important to the life of the pond because in the process of rising to the surface, water dissolves oxygen from the air. The oxygen is then circulated back to the bottom of the pond which allows the aquatic life to survive throughout the year. A home's heating system is an excellent example of convection (circulation of air). RADIATION Once again the main idea is the transfer of heat between two substances of differing temperatures. However, unlike conduction and convection which occur through solids, liquids or gases, radiation occurs in the absence of matter. Heat radiation can travel through a vacuum or air and does not require any particles or vibration for its transmission. Heat radiation is given off by warm objects such as the sun, a heat lamp or even the human body. Objects heat up in sunlight because the heat is being transferred from the sun in the form of radiation. It travels through the vacuum in space and through the air in the atmosphere to the object where the radiation speeds up the particles in the object. Various substances absorb radiant heat at differing rates. The colour of an object affects the amount of radiant heat that is absorbed. (This is the focus of the investigation in Part C). Black objects absorb all the colours of light and reflect none. Dark colours tend to absorb more radiant heat than light colours. In Grade Four, students studied the colour spectrum. They learned that certain objects absorb specific colours in the spectrum and reflect others. It is the reflected colour that gives objects their colour. This concept will help them understand radiation, because they know that many light sources give off visible light and heat radiation. The surface of the object is also a factor affecting the absorption of heat. The rougher the surface, the more radiant heat is absorbed. All objects radiate and absorb heat continuously. The rate at which they do so differs depending on the colour, temperature and texture of the object. Tin foil has been used in the Part D activity because it can be crumpled to create many different surface textures. If you are unable to create enough "textured" difference in the surface using tin foil, try sandpaper, or cotton fabrics such as denim, or corduroy. (Try to keep the colour the same, so it is not a factor). Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-29

36 Heat Transfer Heat Subtask 5 Energy and Control An Integrated Unit for Grade 7 FROZEN ICE TREATS BOX CHALLENGE 270 mins Frozen ice treats are often only available in the summer months so you may want to stock up while they are available. If you can not get frozen ice treats, an ice cube in a freezer bag that can be sealed will also work. Start collecting tissue boxes for this challenge before you begin the unit. Teacher Reflections Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-30

37 Energy Transformation and Heat Systems Heat Subtask 6 Energy and Control An Integrated Unit for Grade mins Description Students will explore the relationship between heat and energy transformations. Students will explore everyday items that produce heat as a desired energy form, or as a byproduct, and will be introduced to sensory systems that manage or control heat energy. Expectations 7s73 7s74 identify different forms of energy that can be transformed into heat energy (e.g., mechanical, chemical, nuclear, or electrical energy); explain how mechanical systems produce heat (e.g., by friction), and describe ways to make these systems more efficient (e.g., by lubrication); Groupings Students Working As A Whole Class Students Working In Pairs Students Working In Small Groups Teaching / Learning Strategies Direct Teaching Discussion Note-making Research Inquiry Assessment Assessment Strategies Questions And Answers (oral) Select Response Assessment Recording Devices Anecdotal Record Teaching / Learning Part A: Energy Transformations (60 minutes) Before the class the teacher should: - photocopy the blackline master, Energy Transformations (BLM 7.6.1) (One per student). - make the overhead transparencies. - collect as many energy producing devices as possible. (e.g., small electric motor, hair dryer) Brainstorm to identify different kinds of energy. Create a list on the blackboard. The list should include: -light energy; -heat energy; -kinetic energy; -sound energy; -chemical energy; -electrical energy; -mechanical energy. 2. Reinforce the concept that energy can neither be created nor destroyed. It can be converted from one form to another. Therefore energy is never lost, it is simply changed to another form of energy. Ask the students to provide examples. For example: Light energy from the sun is converted into kinetic energy and heat energy. Electrical energy converted in heat energy and light energy by a light bulb. 3. Hold up a hair dryer. Ask them to identify the kind of energy that makes it "run" (electrical energy). Now ask the students what kind of energy the hair dryer produces (sound, heat and kinetic energy). Ask the Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-31

38 Energy Transformation and Heat Systems Heat Subtask 6 Energy and Control An Integrated Unit for Grade mins students which of these energies is necessary to dry hair (kinetic and heat energy). Ask the students which energy was unnecessary (sound). In any device, there are desired energies and byproduct energies. The most efficient devices try to reduce byproduct energy to maximize the production of the "desired energy". Byproduct energy "can never be totally eliminated". 4. Tell the students that they will be examining common devices in the room, or observe some practical applications of energy transformation. They will identify the "input" energies and the "output" energies. At the end of their investigations they will make some generalizations about the relationship between energy transformation and heat. 5. Distribute the blackline master Energy Transformations (BLM 7.6.1). Have the students work through the examples of heat transformations. This can be done individually, with a partner or in small groups. Examples m) and n) have been left blank to provide flexibility for teachers wishing to provide their own examples. 4. The student handout may be collected for evaluation. Teacher answer sheet is BLM 7.6.2, Energy Transformations - Teacher Answers. Part B: Heating Systems (160 minutes) 1. Students will be introduced to examples of feedback control systems. Using the brainstorming technique they will work in pairs or small groups to generate ideas which explain why these systems are necessary and how they work. 2. Show the overhead illustrating a typical feedback control system Typical Feedback System (BLM 7.6.4). 3. Present the students with a copy of the Memo (BLM 7.6.6) issued by the Ministry of Energy and Control. Students should work in pairs or small groups. Each company (pairing) will begin by researching feedback systems using BLM 7.6.5, Research Proposal. The students will then continue their research focusing on the environmental concerns and issues which relate to their product. The team will research and design their own "feedback system". 4. The research should be conducted in stages, if possible. This will allow the students the opportunity to fully research and explore each section. It will also allow the teacher to monitor and adjust the research proposal as it develops. 5. Research Feedback Component - Have the students draw, label, and provide examples of the feedback systems they uncovered in their research. 6. Environmental Component - Have the students focus on specific feedback systems explored during their research pointing out any positive and negative environmental concerns or issues. 7. Design Component - Based on their research the students will be required to design a feedback system to suit a purpose. 8. Have each group complete Heat Feedback Control Systems (BLM 7.6.3) and submit for evaluation. Adaptations Teachers are encouraged to: - involve the student in setting goals for work completion; Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-32

39 Energy Transformation and Heat Systems Heat Subtask 6 Energy and Control An Integrated Unit for Grade mins - encourage risk taking; - provide varied opportunities for peer and/or group interactions (e.g., cooperative learning, sharing); - teach visual strategies for journal writing and/or note making (e.g., use of diagram/picture to represent content); - provide advance organizers to structure content (e.g., outlines, subtitles, paragraph frames); - encourage the use of lists, advance organizers, personal planner for personal organization; - allow opportunities for alternatives to writing (e.g., graphic representations, drama, media presentations, timelines, collages). Resources BLM BLM BLM BLM BLM BLM blm cwk blm cwk blm cwk blm cwk blm cwk blm cwk a variety of energy producing devices Notes to Teacher Teacher Reflections Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-33

40 Culminating Task Heat Subtask 7 Energy and Control An Integrated Unit for Grade mins Description In the culminating task students will apply their understanding of heat to the design and construction of a lunch box that maintains functional temperature zones and does not allow heat transfer between the zones. Expectations 7s52 7s53 7s54 demonstrate understanding that heat is a result of molecular motion; identify, through experimentation, ways in which heat changes substances, and describe how heat is transferred; explain how the characteristics and properties of heat can be used, and identify the effect of some of these applications on products, systems, and living things in the natural and human-made environments. Groupings Students Working In Pairs Teaching / Learning Strategies Brainstorming Collaborative/cooperative Learning Model Making Experimenting Assessment Assessment Strategies Exhibition/demonstration Performance Task Self Assessment Assessment Recording Devices Rubric Teaching / Learning The Summative Task - The Lunch Box of the Future 1. Brainstorm to develop a list of the concepts students learned while exploring heat. Students may wish to refer to their science and technology journals. 2. Discuss the importance of heat in every day life. 3. Use BLM 7.7.1, The Lunchbox of the Future to introduce the summative task. It explains that the "Snack'm" Lunch Box Company needs submissions for a "Lunch Box of the Future" that does not use expanded polystyrene as its insulator. Students will work in partners. 4. Pages 2 and 3 of BLM 7.7.1, The Lunchbox of the Future list all the criteria for the design challenge. Distribute these pages to students. Review the criteria required for design, testing and presentation. Ensure that students understand each set of criteria and how each relates to the overall process. 5. Distribute BLM 7.7.2, Testing Trials which provides a table students will use to collect data while performing the trial testing and a list of questions related to the process. After each trial, students are required to respond to specific questions and to record this information in their science and technology journals. Remind students of the importance of measuring accurately and of recording information precisely. Ensure students know what is expected in a thorough answer. 6. Distribute a copy of the evaluation rubric BLM 7.7.4, Lunchbox Rubric to each student. Discuss each of the components of the rubric and how it relates to the lunch box proposal. Allow the groups to discuss the evaluation criteria. Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-34

41 Culminating Task Heat Subtask 7 Energy and Control An Integrated Unit for Grade mins 7. Once students have had at least one class period to begin working on their assignment establish timelines and due dates. Post this information in a visible location. 8. Review the importance of setting goals and remind students to use their time wisely. Post BLM Process Checklist. Make a copy for each group. Discuss the checklist. 9. Students now have all of the handouts related to the assignment which include: the scenerio "The Lunch Box of the Future"; the proposal criteria (two pages); the pages for recording testing trials (two pages) and the process checklist. Have students attach all of these pages together and write a note to their parents about the assignment. The note should include: the names of the people in their group, the date for the submission of a written presentation; the date of the oral presentation; a rough outline of their project plan. 10. Each student will be required to get a parent/guardian signature on each of the pages to confirm that parents are aware of the assignment. 11. Bring the class together on a regular basis to share successes and to discuss problems. Highlight some of the checks on the process checklist to ensure that everyone is on track for completing the assignment. 12. On the final testing day, students should record initial temperatures and then leave their lunch box untouched for four hours. They will have to create their own recording table based on the table they used for their trial testing. Using this information, they will also have to create a graph which illustrates the results. 13. Students will then need some time to create and finalize both their written and oral presentations. If possible, teachers may wish to bring in "executives" from the "Snack'm" company to listen to the proposals. The "executives" could be other teachers or administrators from the school. 14. After all of the groups have presented, have students discuss which proposal was the most effective. Ask for feedback about the assignment and the value of the process. Adaptations Teachers are encouraged to: - involve the student in setting goals for work completion; - encourage risk taking; - provide varied opportunities for peer and/or group interactions (e.g., cooperative learning, sharing); - teach visual strategies for journal writing and/or note making (e.g., use of diagram/picture to represent content); - provide advance organizers to structure content (e.g., outlines, subtitles, paragraph frames); - encourage the use of lists, advance organizers, personal planner for personal organization; - allow opportunities for alternatives to writing (e.g., graphic representations, drama, media presentations, timelines, collages). Resources BLM BLM BLM BLM blm cwk blm cwk blm cwk blm cwk Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-35

42 Culminating Task Heat Subtask 7 Energy and Control An Integrated Unit for Grade 7 Notes to Teacher 240 mins Teacher Reflections Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:06 PM Page C-36

43 Appendices Heat Energy and Control Resource List: Black Line Masters: Rubrics: Unit Expectation List and Expectation Summary: Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:14 PM

44 Heat Energy and Control An Integrated Unit for Grade 7 Resource List Page 1 Blackline Master / File BLM 7.uw.1 blm 7.uw.1.cwk BLM 7.uw.2 blm 7.uw.2.cwk BLM 7.uw.3 blm 7.uw.3.cwk BLM 7.uw.4 blm 7.uw.4.cwk BLM 7.uw.5 blm 7.uw.5.cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk Unit Unit Unit Unit Unit ST 1 ST 2 ST 2 ST 2 ST 2 ST 3 ST 3 ST 3 ST 3 ST 4 ST 4 ST 4 ST 4 ST 4 ST 4 ST 5 ST 5 ST 5 ST 5 BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk BLM blm cwk ST 5 ST 5 ST 5 ST 5 ST 5 ST 5 ST 6 ST 6 ST 6 ST 6 ST 6 ST 6 ST 7 ST 7 ST 7 ST 7 Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:17 PM Page D-1

45 Heat Energy and Control An Integrated Unit for Grade 7 Resource List Page 2 Print Be Safe Unit Science Teachers' Association of Ontario A safety manual matched to the Ontario curriculum. Available from STAO. For further information refer to STAO website Material aluminum foil ST 5 corrugated cardboard ST 5 cotton balls (large) ST 5 cotton garment (clean old T-shirt or socks) ST 5 drink crystals ST 4 extruded polystyrene (approx 1.5 cm thick) ST 5 frozen ice treats ST 5 masking tape ST 5 paper (for crumpling) ST 5 plastic bubble wrap ST 5 sawdust or confetti ST 5 tissue boxes ST 5 wooden stir sticks ST 3 wool garment (clean old sweater or socks) ST 5 Equipment / Manipulative 100g of glycerin or liquid soap ST 3 2 L pop bottles or Erlenmeyer flask ST 4 50g (or equal mass) of various metals ST 3 a variety of energy producing devices ST 6 aluminum foil ST 3 an aluminum block or pot ST 3 balance scale ST 3 ball ST 4 beakers ST 3 beakers ST 4 beakers ST 5 beakers/containers/pails ST 2 candle (optional light source) ST 5 containers/pails ST 3 dish cloth ST 4 elastics ST 4 expanded polystyrene cups ST 3 felt of 4 different colours ST 5 heat resistant mats ST 4 hot plate ST 5 hot plates ST 3 hot plates ST 4 ice ST 2 ice ST 4 lamps ST 5 lamps to heat water and sand ST 2 oven mitts ST 4 pails/large containers ST 4 petrie dishes ST 4 radiometer ST 5 retort stand with clamp ST 5 retort stand with ring apparatus ST 4 retort stands ST 3 safety glasses ST 3 sand ST 2 small, non-latex spherical balloons ST 4 spoons (metal/wood/plastic) ST 5 stirring rod ST 3 stop watches ST 4 thermometer clamp ST 3 Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:17 PM Page D-2

46 Heat Energy and Control An Integrated Unit for Grade 7 Resource List Page 3 thermometers ST 2 thermometers ST 3 thermometers ST 4 thermometers ST 5 tongs ST 3 toy car tracks (optional activity) ST 5 toy cars (optional activity) ST 5 Written using the Ontario Curriculum Unit Planner 2.51 PLNR_01 March, 2001* Open Printed on Oct 25, 2001 at 2:07:17 PM Page D-3

47 SAFETY CONTRACT Science and Technology ALWAYS: 1. wear safety glasses. 2. act appropriately and responsibly. 3. treat equipment with care. 4. tuck in all baggy clothing and tie back hair. 5. stay a safe distance away from experiments. 6. follow the teacher s directions EXACTLY (if unsure ask before doing). 7 be alert and stand while conducting experiments. 8. maintain an appropriate noise level. 9. know where fire equipment and fire exits are located. 10. KEEP HEAT SOURCES AWAY FROM CHEMICALS/AEROSOL CANS. NEVER: 1. remove any materials or equipment from the lab. 2. ingest chemicals. 3. touch a heat source directly. 4. eat or drink in the lab. 5. play with lighters, matches or lab equipment. 6. get too close to heat source. 7. abuse equipment. 8. leave an experiment unattended. 9. put liquids directly on the burner or any heat source. 10. conduct any procedure or use any heat source without permission. I have read the Safety Contract. I understand and will follow the rules as stated in the contract. Consequences for not following the rules are outlined in the school s code of conduct. Student s name printed: Student s signature: Teacher: Date: Parent/Guardian signature: Date: BLM 7.1.1

48 The Measurement of Heat Around 1592, Galileo ( ) developed the first air thermometer which used a liquid filled tube. Galileo only compared the rise and fall of the liquid in the tube which was not an accurate measurement. To accurately measure temperature, the tube must be calibrated with a numbered scale of some kind. The design of most thermometers is based on thermal expansion. The liquid found in most thermometers is either mercury or alcohol. The type of liquid used usually depends on the purpose of the thermometer. For example, mercury freezes at -39 ºC so alcohol would probably be used when creating a weather thermometer for very cold areas. Some thermometers are based on the expansion of solids. A bimetallic strip is normally used in thermostats to show temperature change. The longer the bimetallic strip, the greater amount of bending. Very precise thermometers use the expansion and contraction of gases. Gas-based thermometers are rarely used because the temperature range is very limited which makes this type of thermometer impractical for daily usage. Other types of temperature recording devices include an optical pyrometer, and a thermocouple. Each of these devices measures extreme temperatures. An optical pyrometer measures very hot temperatures such as those found when iron melts. Its functioning is based on the colours produced by glowing objects. Similarly, a thermocouple which is a thermoelectric device records extremely hot temperatures such as the temperature of lava. Scientist believe that if matter could be cooled enough, the molecules' movement would be so slow that heat could no longer be transferred from the matter itself. This idea is called absolute zero and could be reached at a temperature of -273 ºC. Absolute zero has never been attained although scientists have come within degrees Celsius of doing so. Temperature scales are based on the concept of fixed points. These are points where specific substances freeze or boil. The substance normally used is PURE water. Therefore, most scales are based on an equally calibrated scale between water's freezing point and water's boiling point. Absolute zero is also considered a fixed point. BLM 7.2.1

49 TYPES OF TEMPERATURE SCALES The two most commonly used temperature scales in the world are the Celsius (ºC) and the Kelvin (K) scales. Celsius - created by Anders Celsius ( ) based on increments of ten. The fixed points used are water's freezing point at 0 ºC and water's boiling point at 100 ºC. Kelvin - created by Lord Kelvin ( ) so that there would be no negatives on the scale. The lowest temperature is absolute zero at 0 K. Therefore, water would freeze at K Temperature is a physical quantity which gives us an idea of how hot or cold an object is. The temperature of an object depends on how fast the atoms and molecules, which make up the object can shake, or oscillate. As an object is cooled, the oscillations of its atoms and molecules slow down. For example, as water cools, the slowing oscillations of the molecules allow the water to freeze into ice. In all materials, a point is eventually reached at which all oscillations are the slowest they can possibly be. The temperature which corresponds to this point is called absolute zero. Note that the oscillations never come to a complete stop, even at absolute zero. The Celsius scale sets the freezing point of water at 0 ºC and the boiling point at 100 ºC. On the Celsius scale, absolute zero corresponds to a temperature of -273 ºC. Scientists - especially those who study what happens to things when they become very, very cold - commonly use the Kelvin scale, with temperatures measured in Kelvin (K). This scale uses the same temperature steps as the Celsius scale, but is shifted downward. On this scale, water freezes at 273 K and boils at 373 K. Only on the Kelvin temperature scale does absolute zero actually fall at 0 K. BLM 7.2.1

50 When handling a thermometer I must: Taking and Recording Temperatures When taking the temperature of a substance, I must: The temperature scale we are using is: Be sure to include the proper units. PREDICTION of temperature ACTUAL temperature Room temperature Temperature of glass at window Temperature of cold tap water run for 10 seconds Temperature of a pail of sand at room temperature Temperature of ice water Temperature under arm (over clothes, thermometer held under the arm) Temperature behind knee Temperature of water under lamp for 10 minutes Temperature of a pail of sand under lamp for 10 minutes BLM 7.2.2

51 Matching Temperatures TEMPERATURE RANGE a hot summer day boiling water a cold winter day room temperature normal cooking temperature inside oven ice cream freshly made hot chocolate temperature of a typical refrigerator freezer temperature of a typical refrigerator bath water normal body temperature ice ANSWERS: 300 to 500 o C -5 to 0 o C 100 o C 40 to 45 o C -5 to -25 o C 70 to 90 o C 0 o C 25 to 35 o C 18 to 22 o C -10 to -20 o C 5 to 10 o C 37 o C (may vary due to exposure to extreme cold or illness) Temperature Facts! The temperature of the centre of the Sun is o C The temperature of the centre of the Earth is o C The temperature of dry ice is -210 o C BLM 7.2.3

52 Matching Temperatures (teacher copy) Temperature or Temperature Range a hot summer day boiling water a cold winter day comfortable room temperature normal cooking temperature inside oven ice cream freshly made hot chocolate temperature of a typical refrigerator freezer temperature of a typical refrigerator bath water normal body temperature ice 25 to 35 o C 100 o C -5 to -25 o C 18 to 22 o C 300 to 500 o C -5 to 0 o C 70 to 90 o C -10 to -20 o C 5 to 10 o C 40 to 45 o C 37 o C (may vary due to exposure to extreme cold or illness) 0 o C Temperature Facts! The temperature of the centre of the Sun is 15,000,000 o C The temperature of the centre of the Earth is 4,000 o C The temperature of dry ice is -210 o C BLM 7.2.4

53 The Amount of Heat in Hot Water Use the I.N.S.I.T.E. method as laid out below to develop and test a hypothesis that compares the heat capacity of various volumes of a liquid. I: Identify the problem Is there a difference between the amount of heat in a small volume of water compared to a large volume of water? N: Narrow the problem What type of materials will be needed? What are the variables in the problem? What factors should be kept constant to ensure a fair test? What volumes of water will we use? S: State the hypothesis Make a scientific guess which proposes a solution to the problem above. I hypothesize that: I: Investigate and gather information Materials: safety glasses, stirring rod, thermometer, 50 ml or 100 ml beaker, expanded polystyrene cup, tongs Variables: Procedure: Pour about 50 ml of cool water into an expanded polystyrene cup. 1. Using a pen, place a line on the inside of the expanded polystyrene cup to mark the water level. 2. Measure and record the temperature of the cool water in the cup. Keep the thermometer in the cup, holding it securely with one hand. 3. Take tongs, a 50 ml or 100 ml beaker, and the expanded polystyrene cup with the thermometer to the hot water container. 4. Use the thermometer in the container to record the temperature of the water in the hot water container. 5. Scoop out about 40 ml of the hot water and pour it into the cup of cool water. 6. Stir the water with the stirring rod. When the temperature has stabilized, measure and record the temperature. 7. Pour the mixture into a sink or dispose of it according to your teacher s instructions. 8. Refill the expanded polystyrene cup with the same volume of cool water as in step 1. Use the mark on the inside of the cup as a guide. 9. Repeat steps 3, 4 and 5. BLM 7.3.1

54 10. Repeat steps 6, 7 and 8 using 80 ml of hot water instead of 40 ml. 11. Clean up your lab station and put away all equipment. 12. Compare the final temperature of the two mixtures. Which has a higher final temperature? 13. Explain why the final temperature of the one mixture is higher than the other mixture. T: Test the hypothesis Follow the procedure above to test your hypothesis. E: Examine the results and write a conclusion COOL WATER Volume in millilitres COOL WATER Temperature in degrees Celcius HOT WATER HOT WATER MIXTURE Volume in millilitres Temperature in degrees Celcius Final Temperature in degrees Celcius 1. Which mixture had the higher final temperature? 2. Based on your answer to question 1, which mixture do you think contained the greater amount of heat? 3. Which mixture had the greater volume of hot water added to it? 4. Both samples of hot water had the same temperature before they were mixed with cool water. Explain which cup of hot water contained the greater amount of heat before it was added to the cool water and why you think this one had more heat? BLM 7.3.1

55 HEAT CAPACITY Use the I.N.S.I.T.E. method as laid out below to develop and test a hypothesis that compares the heat capacity of various substances. I: Identify the problem Is there a difference between the amount of heat in a small volume of water compared to a large volume of water? N: Narrow the problem What type of materials will be needed? What are the variables in the problem? What factors should be kept constant to ensure a fair test? What volumes of water will we use? S: State the hypothesis Make a scientific guess which proposes a solution to the problem above. I hypothesize that: I: Investigate and gather information Materials: safety glasses Sample materials with similar masses thermometers aluminum zinc expanded polystyrene cups iron rock stirring rods copper tongs Variables: Procedure: Place about 200 ml of cool water in an expanded polystyrene cup. 1. Using a pen, place a line on the inside of the cup to mark the water level in the cup. 2. Take the tongs and the cup of cool water to the hot water station. Grasp the thermometer securely with one hand. 3. Measure and record the temperature of the cool water in the cup just before adding the hot sample. 4. Record the temperature of the water in the large hot water container. 5. Use the tongs to take one of the samples out of the hot water. Shake the sample briefly to remove excess water, and immediately submerge the sample in the cup of cool water. 6. Stir the water using a stirring rod until the temperature stabilizes. 7. Record the final temperature.remove the sample from the cup, clean off the excess water, and record the name of the sample.8 8. Return the sample to its proper location in the hot water container. BLM 7.3.2

56 9. Pour the water out of the expanded polystyrene cup. 10. Repeat steps 1 to 11 for each of the other samples. T: Test the hypothesis Follow the procedure above to test your hypothesis. E: Examine the results and write a conclusion COOL WATER HOT SAMPLE WATER + SAMPLE Temperature (degrees C) Temperature (degrees C) Sample Name Final Temperature (degrees C) Answer the following questions on a separate sheet of paper: 1. a) Which sample caused the highest final temperature? b) Based on the final water temperature, which sample transferred the greatest amount of heat to the cool water? c) The sample which contained the greatest amount of heat, or which transferred the greatest amount of heat is said to have the greatest capacity for holding heat (the greatest heat capacity). Create a chart with two columns. Label one column Prediction and the other column Actual. Have five rows under the titles of each column. List the samples in order of heat capacity from highest to lowest below. 2. a) In each case was the final temperature closer to the initial temperature of the water or the initial temperature of the sample? b) Which changed temperature the most, the cool water or the hot sample? c) What conclusion can you make from the observation in 2b)? 3. On a hot summer day at the beach: a) Which is usually warmer in the daytime, the sand or the water? b) Which has the greater change in temperature from day to night? (sand or water) c) Which has the greater change in temperature from night to day? (sand or water) d) The one with the greater temperature change has the lower heat capacity. Is this the sand or the water? e) The one with the smaller temperature change has the higher heat capacity. Is this the sand or the water? f) Why? BLM 7.3.2

57 Mass, Rate of Temperature Change and Heat Capacity Use the I.N.S.I.T.E. method as laid out below to develop and test a hypothesis that compares the mass of a liquid, the rate of temperature change, and heat capacity. I: Identify the problem Is there N: Narrow the problem What type of materials will be needed? What are the variables in the problem? What factors should be kept constant to ensure a fair test? S: State the hypothesis Make a scientific guess which proposes a solution to the problem above. I hypothesize that: I: Investigate and gather information thermometer retort stand beaker 1. Place the hot plate on a level surface. Do not turn it on. 2. Set up 2 retort stands as shown. 3. Fill one beaker with 100ml of tap water and place it on an element. Fill another beaker with BLM hot plate

58 3. Fill one beaker with 100ml of tap water and place it on an element. Fill another beaker with 200 ml of tap water and place it on the other element. Use a balance scale to check that you have 100 g and 200 g of water. 4. Place a thermometer in each beaker of water. (Attach it to the retort stand as shown in the diagram). 5. Take an initial reading of the water temperature. 6. Turn on the hot plate element. 7. Time how long it takes the water in each beaker to reach 70oC. 8. Once the temperature reaches 70oC, turn off the hot plate and remove the beakers with tongs or oven mitts. 9. Record your observations in the chart below. Mass of water (grams) Temperature at Temperature at the start (degrees the end (degrees Celsius) Celsius) Change in Temperature (degrees Celsius) Time (minutes) T: Test the hypothesis Follow the procedure above to test your hypothesis. E: Examine the results and write a conclusion Complete the following on a separate sheet of paper. 1. Compare the start temperature of 100 g of water to the start temperature of 200 g of water. Were they the same? 2. Compare the time it took for each to reach 70oC. Was the rate of temperature change the same for each? 3. Predict what would happen if you conducted the same experiment with 300 g of water? Explain your prediction. 4. How do different masses affect the rate of temperature change? Explain how this relates to heat capacity. BLM 7.3.3

59 Nature of a Liquid, Rate of Temperature Change and Heat Capacity Use the I.N.S.I.T.E. method as laid out below to develop and test a hypothesis that compares the nature of a liquid, the rate of temperature change, and heat capacity. I: Identify the problem Does the nature of a liquid affect the rate of temperature change and the heat capacity of a liquid? N: Narrow the problem What type of materials will be needed? What are the variables in the problem? What factors should be kept constant to ensure a fair test? S: State the hypothesis Make a scientific guess which proposes a solution to the problem above. I hypothesize that: I: Investigate and gather information Materials: hot plate, retort stand, balance scale, beaker, thermometer, stirring rod, water, glycerin or liquid soap. retort stand thermometer beaker hot plate 1. Set up the materials as shown in the drawing. The steps are as follows. 2. Turn on the hot plate, being careful not to touch the element. 3. Measure out 100 g of the liquid. Check the mass using a balance scale. 4. Place the beaker carefully on the hot plate and place the thermometer into the liquid. 5. Stir the liquid carefully with a stirring rod. 6. When the temperature reaches 30oC, begin taking readings every 30 s until the temperature reaches 60oC. Record the temperature on your chart. 7. Once the liquid reaches 60oC, turn the hot plate off. T: Test the hypothesis and record observations BLM 7.3.4

60 Follow the procedure above to test your hypothesis and record your observations. Create a line graph to display your results. Time Interval (seconds) 30 s 60 s 90 s 120 s 150 s 180 s Temperature (degrees Celsius) water glycerin or liquid soap E: Examine the results and write a conclusion 1. Looking at the line graph, which liquid took the longest to heat up? Which took the shortest time to heat up? 2. How might you explain the results? 3. What conclusion can you make about the effect of the nature of liquids on the rate of temperature change? Explain how this relates to heat capacity. BLM 7.3.4

61 PARTICLES AND STATES OF MATTER States Relative Position Description Solid (ice) Liquid (water) Gas (water vapour) BLM 7.4.1

62 Changes in the Volume of A Liquid Use the I.N.S.I.T.E. method to develop and test a hypothesis that the volume of a liquid changes with temperature changes. I: Identify the problem Is there a difference in the volume of a liquid when it is immersed in water of varying temperatures? N: Narrow the problem Remember, temperature is a way of measuring the average energy of particles in an object. What equipment will you use? Where is the liquid in the equipment you are using? What happens to the volume of the liquid? How do you know? S: State the hypothesis Make a scientific guess which proposes a solution to the problem. I hypothesize that the approximate temperatures when the thermometer is immersed in the following will be: Ice Water (degrees Celsius) Tap Water (degrees Celsius) Hot Water (degrees Celsius) I hypothesize that the the temperature of the water that the thermometer is immersed in the the liquid in the thermometer will be. This means that there is volume of liquid in the thermometer. I think this happens because I: Investigate and gather information Materials: one dishcloth for spills, two empty beakers, one beaker filled with approximately 150 ml of tap water, one thermometer, one stopwatch (wrist watches or wall clock) 1. Go to your assigned station and ensure that you have the proper equipment. 2. One group member will start timing as soon as another group member inserts the thermometer into the beaker of tap water. After two minutes, each member will read the thermometer and then record the temperature of the water in the chart below. Remember to be accurate and read the temperature with the thermometer at eye level. 3. Using one of the empty beakers, one group member will get 150 ml of ice water from the teacher. 4. Repeat step 2 using the beaker of ice water. 5. Using the other beaker, one group member will get 150 ml of hot water from the teacher. BLM 7.4.2

63 6. Repeat step 2 using the beaker of hot water. T: Test the hypothesis Follow the procedure above to test your hypothesis. E: Examine the results and write a conclusion Time (minutes) Tap Water (degrees Celsius) Ice Water (degrees Celsius) Hot Water (degrees Celsius) two minutes 1. What effects do heating and cooling have on the volume of a liquid? How do you know? When explaining your results and writing your conclusions, try to use the following words: heat, temperature, volume, expansion, contraction and liquid. BLM 7.4.2

64 Changes in the Volume of A Solid Use the I.N.S.I.T.E. method to develop and test a hypothesis that the volume of a solid changes with temperature changes. I: Identify the problem Is there a difference in the volume of a solid when immersed in water of varying temperatures. N: Narrow the problem Remember, temperature is a way of measuring the average energy of particles in an object. What equipment will you use? What equipment can be classified a solid? What happens to the volume of the solid? How do you know? S: State the hypothesis Hypothesis 1: When the ball is immersed in cold water its volume will because Hypothesis 2: When the ball is immersed in hot water its volume will because Hypothesis 3: When the ring is immersed in cold water its volume will because I: Investigate and gather information Materials: ball, retort, hot water, cold water and ring apparatus 1. Immerse the ball in hot water. Record what happens when the teacher tries to pass the ball through the ring. 2. Immerse the ball in cold water. Record what happens when the teacher tries to pass the ball through the ring. 3. Immerse the ball in hot water and the ring in cold water. Record what happens when the teacher tries to pass the ball through the ring. BLM 7.4.3

65 T: Test the hypothesis Follow the procedure above to test your hypothesis. E: Examine the results and write a conclusion 1. Observation 1: When the ball was immersed in hot water 2. Observation 2: When the ball was immersed in cold water 3. Observation 3: When the ball was immersed in hot water and the ring was immersed in cold water 4. On a separate sheet of paper, compare and explain the three observations that were made.what effects do heating and cooling have on the volume of a solid? How do you know? When explaining your results and writing your conclusion, try to use the following words: heat, temperature, volume, contraction (decreases), expansion (increases) and solid. BLM 7.4.3

66 Changes in the Volume of A Gas Use the I.N.S.I.T.E. method below to develop and test a hypothesis that the volume of a gas changes with temperature changes. I: Identify the problem Is there a difference in the volume of a gas when it is immersed in water of varying temperatures. N: Narrow the problem Remember, temperature is a way of measuring the average energy of particles in an object. What equipment will the teacher use? Why is this an appropriate choice? Where is the gas found in the apparatus? What happens to the volume of a gas? How do you know? S: State the hypothesis Hypothesis 1: What will happen to the deflated balloon when it is surrounded by cold water? Hypothesis 2: What will happen to the deflated balloon when it is surrounded by hot water? I: Investigate and gather information 1. Place heat resistant mats on the demonstration desk. 2. Place a retort stand on each mat. 3. Place a container deep enough to hold one empty 1.5 L plastic pop bottle and approximately 500 ml of water on the base of each retort stand. 4. Place one empty 1.5 L plastic pop bottle in each container. 5. Inflate the balloons several times to stretch them. 6. Place a deflated balloon around the neck of each bottle. 7. Clamp the neck of each bottle to a retort stand. Clamping prevents the bottle from floating once the water is poured into the container. 8. Prepare and store approximately 1 L each of ice water and 1 L of hot water in separate containers. 9. Carefully pour hot water into one of the containers, so the water fills up around the bottle. 10. Carefully pour ice water into the other container so that the water fills up around the bottle. 11. Let the bottles sit in the water for approximately 10 minutes. 12. Observe what happens to each balloon. BLM 7.4.4

67 13. Record what happens to each balloon. 14. Wearing an oven mitt, carefully remove each bottle and place each on a heat resistant placemat. 15. Observe the bottles for 3 minutes. 16. Record what happens to each of the balloons. T: Test the hypothesis Follow the procedure above to test your hypothesis. E: Examine the results and write a conclusion 1. What happened to the deflated balloon when it was surrounded by hot water? 2. What happened to the deflated balloon when it was surrounded by ice water? 3. Use the knowledge you acquired from two previous investigations (the changes in the volume of a liquid and the changes in the volume of a solid) to explain how heating and cooling affect the volume of a gas. BLM 7.4.4

68 THE PARTICLE THEORY Use the I.N.S.I.T.E. method below to develop and test a hypothesis that examines the relative position of water particles (molecules) in liquid with two different temperatures. I: Identify the problem Is there a difference in the distance between of particles of water when the liquid has more or less heat energy applied to it? N: Narrow the problem What type of materials will be needed? What are the variables in the problem? What factors should be kept constant to ensure a fair test? S: State the hypothesis Make a scientific guess which proposes a solution to the problem above. I hypothesize that: I: Investigate and gather information 1. Place two petrie dishes side-by-side on a sheet of white paper. Make sure the paper is on a solid surface to avoid any movement. 2. Pour cold water in one dish and an equal amount of hot water in the second dish. Wait for about 30 s for the water to settle. 3. Drop one drink crystal or other dark soluble substance, into the centre of each dish and observe. 4. After one minute, make a sketch of what happened and record your observations. 5. Every minute for four minutes, make a sketch of the expanding coloured area in each dish to illustrate the movement of the colour in cold and hot water. T: Test the hypothesis Follow the procedure above to test your hypothesis. E: Examine the results and write a conclusion BLM 7.4.5

69 Using the following template, on a separate sheet of paper sketch the appearance of the colour as it moves outward in the cold water and in the hot water. Do this every minute for a total of four minutes. Be careful not to touch or move the dish at any time. MINUTE (one/two/three or four) Cold water Hot water 1. Did the colour spread out the fastest in cold water or hot water? 2. Examine the results of your test. On a separate sheet of paper, write a conclusion which outlines what you learned in this investigation. In your conclusion write a statement that relates the ability for the colour to spread to the relative position of the water particles. BLM 7.4.5

70 THE KINETIC MOLECULAR THEORY HEAT ENERGY HEAT ENERGY Heat energy is converted to kinetic energy. Collisions cause particles to be knocked further from each other. HEAT ENERGY HEAT ENERGY Particles nearer the heat source speed up causing collisions and increasing distance between particles. Further from the source, the energy is reduced, decreasing the distance between the particles. As the heat energy applied increases, the further from the source this energy is distributed. BLM 7.4.6

71 Conducting an Experiment and Variables On a separate sheet of paper, answer the following questions: 1. What is a variable in a science experiment? 2. Explain what it means to conduct a valid science experiment. 3. During an experiment, how many variables should you change or manipulate? Explain. 4. What does it mean to control variables? 5. Create a chart like the one below leaving enough space for your answers. Name 3 variables you should always control. How would you control them? Variable How it can be controlled 6. Create a chart like the one below leaving enough space for your answers. Name 3 examples of variables that are very difficult to control. Why is it difficult to control them? Variable Why it is difficult to control BLM 7.5.1

72 Conducting an Experiment and Variables (teacher answers) **answers will vary** 1. What is a variable in a science experiment? A variable is any part of the experiment including equipment, substances, environment, procedures, and etc. that may vary or change while conducting an experiment. 2. Explain what it means to conduct a valid science experiment. The scientist has planned a well-thought-out idea and has tried to follow good and logical procedures and has tried to ensure that s/he has taken into account all of the variables and s/he has tried to be as precise as possible. The experiment should also be able to be duplicated and the results that are attained should be similar. 3. During an experiment, how many variables should you change or manipulate? Explain. You should only change one variable at a time so that you can see how changing this one variable impacts on the final results. If you change too many variables at one time, you can not tell which one had an impact on the results. For example, if you have an allergy, the doctor would expose you to one substance at a time to figure out what is causing your allergic reaction. 4. What does it mean to control variables? It means that you realize they are important and you try to keep them the same through the experiment. For example, you may wish to use all the same size and type of container, the same temperature, type and quality of substance. Any variance of these may cause your results to be invalid because once again you do not know what caused the change in results. 5. Name 3 variables you should always control. How would you control them? Variable How it can be controlled quantity of a substance type of equipment measurement of time & temperature using appropriate measurement tools and measuring accurately ensure same size, made of the same materials, same quality use accurate watches and thermometers, set specific times & temperatures 6. Name 3 variables that are very difficult to control. Why is it difficult to control them? Variable Why it is difficult to control atmosphere temperatures such as air, humidity, pressure accuracy of measurement tools human responses such as reflexes, and reading instruments environmental but can take into account things such as baking at high altitudes depends on the quality of equipment such as thermometers, scales, etc. human error when reading clock, or measuring BLM 7.5.2

73 Metal Conductors Use the I.N.S.I.T.E. method below to investigate the rate at which different metals conduct heat. I: Identify the problem N: Narrow the problem S: State the hypothesis Make a scientific guess which proposes a solution to the problem above. I hypothesize that: I: Investigate and gather information T: Test the hypothesis Follow the procedure above to test your hypothesis. E: Examine the results and write a conclusion BLM 7.5.3

74 Examine the results of your test. Write a conclusion that outlines what you learned in the investigation. In your conclusion write a statement about the law of reflection. BLM 7.5.3

75 Spiral Template BLM 7.5.4

76 CONVECTION QUESTIONS Answer the following on separate sheet(s) of paper. 1. Define: a) convection b) convection current 2. How does convection help heat your favourite room? Sketch the room. Show where the heat vents are located and label the diagram to show how the room is heated. 3. Why do basements usually feel cooler than the rest of the building? 4. Find the location of your dwelling s thermostat control. Why was it installed in this location? Think about convection and use what you have learned in your answer. 5. Explain the process of heating soup on the stove. Start with the heat given off by the stove s element and proceed from there, step by step, until the soup itself is boiling. Use a precise written description and include diagrams to illustrate your explanation. 6. What happens to the temperature of the soup when you turn off the stove s element? Explain why this happens. BLM 7.5.5

77 CONVECTION (teacher answers) I. Define: a) convection Convection is the transfer of heat energy which occurs when heated liquid or gas particles travel from one place to another. b) convection current Convection current is the circular pattern created when heat energy is transferred between particles. 2. How does convection help to heat your favourite room? Sketch the room. Show where the heat sources are located. Explain how the room is heated. Example of heating from heat vent: Hot air is blown out of the furnace duct. If it is hotter than the air in the room, it rises until it reaches the ceiling. It travels across the ceiling, mixing with the cooler air in the room. As this air cools, it falls and travels across the floor. It ends up near the furnace vent which is still blowing out hot air. The hot air being blown out of the vent begins to heat up the cooler air. The warm air rises and the whole process starts over again. This process of circulation (convection) continues until the room (the sensor in the room) reaches the temperature set on the thermostat. SKETCHES WILL VARY BUT THE CONVECTION CURRENT SHOULD BE LABELLED. 3. Why are basements usually cooler than the rest of the building? Hot air rises and cooler air falls. As well, basements are usually constructed out of cement and are not necessarily insulated as well as other parts of the building. 4. Find the location of your dwelling s thermostat control. Why was it installed in this location? Think about convection and use what you have learned in your answer. It is probably located on the main floor of the building in a central location. If you set the thermostat at 20 degrees Celsius, the furnace will turn off when the temperature on the main floor reaches 20 degrees. There may be a slight variation in temperature in rooms some distance away from the thermostat, but the average temperature on the main floor would be about 20 degrees Celsius. 5. Explain the process of heating soup on the stove. Start with the heat given off by the stove s element and proceed from there, step-by-step, until the soup is boiling. Use a precise written description and include diagrams to illustrate your explanation. Heat energy is transferred from the stove s element to the bottom of the pot by conduction. As the bottom of the pot gets hotter, it warms up the soup (by conduction). Because the soup particles BLM 7.5.6

78 are warming up, they begin to expand and spread out across the bottom of the pan. Since this bottom layer of soup is hotter, it is less dense and rises. Once it rises, it comes in contact with pockets of cooler soup and the cooler soup pockets are pushed to the sides of the pot. Because they re cooler, they end up falling to the bottom of the pot where they mix with the warm soup which is being heated by conduction. The warmer soup gets pushed to the centre of the pot and rises to the surface. A convection current of soup is created. The process continues as long as there is heat being transferred from the element to the pot, or until all the soup (liquid) evaporates and there is no soup left in the pot. SKETCHES MAY VARY BUT SHOULD INCLUDE THE CONTINUOUS CONVECTION CURRENT LABELLED WITH APPROPRIATE ARROWS. 6. What happens to the temperature of the soup when you turn off the stove s element? Explain why this happens. Once the element is turned off, there is not heat energy being conducted to the bottom of the pot. The convection current gradually gets cooler and cooler because no heat energy is being added. Eventually no heat energy is transferred at all and no convection occurs. BLM 7.5.6

79 Heat from Radiation Use the I.N.S.I.T.E. method below to develop an investigation to determine how the surface colour of a material affects the amount of radiant energy material absorbed and converted into heat. I: Identify the problem Is there: N: Narrow the problem S: State the hypothesis Make a scientific guess which proposes a solution to the problem above. I hypothesize that: I: Investigate and gather information T: Test the hypothesis Follow the procedure above to test your hypothesis. BLM 7.5.7

80 E: Examine the results and write a conclusion Examine the results of your test. Write a conclusion that outlines what you learned in the investigation. In your conclusion write a statement about the effects of colour on radiant energy absorption and conversion to heat. BLM 7.5.7

81 Heat Transfer in Everyday Life Brainstorm examples of heat transfer. Indicate whether heat is transferred by conduction, convection or radiation. Heat Transfer Type of Transfer Explanation of Why it is this Type BLM 7.5.8

82 THE FROZEN ICE TREAT BOX CHALLENGE The Situation Your teacher has planned a trip to the beach as part of the unit on HEAT. As your class leaves the school the teacher gives each student a frozen ice treat. You must build an insulated container which will keep the frozen ice treat as cold as possible for as long as possible. The container must be easy to access (it must be easy to get the frozen ice treat in and out of the insulated container). Materials Group 1 - a tissue box - masking tape - corrugated cardboard (60 cm x 24 cm) Group 2 - a tissue box - masking tape - plastic bubble wrap (60 cm x 24 cm) Group 3 - a tissue box - masking tape - aluminum foil (60 cm x 24 cm) Group 4 - a tissue box - masking tape - expanded polystyrene no thicker than 1.5 cm (60 cm x 24 cm) Group 5 - a tissue box - masking tape - cotton balls (large) Group 6 - a tissue box - masking tape - cotton garment (clean T-shirt or socks) Group 7 - a tissue box - masking tape - paper (crumpled) Group 8 - a tissue box - masking tape - wool garment (clean sweater or socks) Procedure 1. Use only the specified materials for your group to build your insulated container. 2. Where necessary, cut material equal to the dimensions of the tissue box. 3. Use only enough insulation material to line the tissue box. 4. Design and create a means by which you can open and close the insulated container to allow for easy access to the frozen ice treat. 5. Affix the insulation material to the tissue box. Be efficient in your use of tape. 6. Show your insulated container to the teacher and request a frozen ice treat for testing purposes. 7. Measure and record the temperature of the interior of the insulated container. Measure and record the temperature of the frozen ice treat. 8. Place the frozen ice treat in the insulated container and leave it for an hour. 9. After an hour remove the frozen ice treat. Measure and record the temperature of the interior of the insulated container. Measure and record the temperature of the frozen ice treat. 10. Open the frozen ice treat and using a measuring cup, measure the amount of liquid that accumulated. Record this information on your chart. 11. Create three line graphs: two showing the change in the temperature of the frozen ice treat, and in the temperature of the interior of the insulated container, and the third showing the volume of liquid which accumulated as the frozen ice treat melted. BLM 7.5.9

83 FROZEN ICE TREAT BOX CHALLENGE TEMPERATURES DATE LENGTH OF TIME ELAPSED INITIAL TEMPERATURE (degrees Celsius) FINAL TEMPERATURE (degrees Celsius) The Interior of the Insulated Container The Frozen Ice Treat FINAL VOLUME OF LIQUID (the amount of liquid in ml within the frozen ice treat package caused by melting) BLM

84 Energy Transformations 1. Each of the following devices or situations, demonstrates a change from one form of energy to another. Fill in the blanks on the left with the form of energy that is used up. This is the input energy. Fill in the blanks on the right with a form of energy that is produced. This is the output energy. The first one has been done for you. Device Situation Energy Used Energy/Energies Produced lightbulb electrical light, heat toaster electric motor fireworks stereo amplifier hair dryer matches lightning geyser j) You eat lunch, and a few hours later you play two hours of your favourite sport. Energy used Energy/Energies Produced k) You put gasoline in a car and drive until it runs out of gas. Energy used Energy/Energies Produced l) While riding a bicycle, you apply the brakes and bring it to a stop. Energy used Energy/Energies Produced m) Other examples of energy conversion: give two class/teacher examples BLM 7.6.1

85 example 1: Energy used Energy/Energies Produced example 2: Energy used Energy/Energies Produced 2. Different forms of energy can be converted to other forms of energy. Is this True or False? 3.a) Look at each example in question one. What one form of energy is produced in all cases? b) What effect might this have on the temperature of the atmosphere? 4. a) Make up two examples of your own to illustrate conversion of energy from one form to another. Show on the left, the form of energy used up and on the right the two or more forms of energy that are produced. example: Energy used Energy/Energies Produced example: Energy used Energy/Energies Produced BLM 7.6.1

86 Energy Transformations Teacher answers 1. Each of the following devices or situations demonstrates a change from one form of energy to another. Fill in the blanks on the left with the form of energy that is used up. This is the input energy. Fill in the blanks on the right with a form of energy that is produced. This is the output energy. The first one has been done for you. Device Energy Used Energy/Energies Produced lightbulb electrical light, heat toaster electrical light, heat and some sound electric motor electrical heat, sound, kinetic fireworks chemical light, heat, kinetic stereo amplifier electrical light, heat, sound hair dryer electrical heat, sound, light, kinetic matches electrical light, heat and some sound lightning electrical light, heat, sound geyser heat heat, kinetic j) You eat lunch, and a few hours later you play two hours of basketball or your favourite sport. Energy used Energy/Energies Produced chemical kinetic, heat k) You put gasoline in your car and drive until it runs out of gas. Energy used Energy/Energies Produced chemical kinetic, heat, sound l) While riding your bicycle you apply the brakes and bring it to a stop. Energy used Energy/Energies Produced kinetic heat and some sound 2. Different forms of energy can be converted to other forms of energy. Is this True or False? true 3. a) Look at each example in question one. What one form of energy is produced in all cases? heat b) What effect might this have on the temperature of the atmosphere? This might increase the temperature of the atmosphere if more and more sources of energy are converted to heat. BLM 7.6.2

87 Heat Feedback Control Systems The following systems regulate heat. Working with a partner or in a small group tell why these systems need to regulate heat and how you think this happens. System Automobile Cooling System Why/How it is controlled Toaster Settings Air Conditioning at home/school Heating at home/school Human body system BLM 7.6.3

88 Typical Feedback System Sensor Furnace turned off or on depending on the instruction Signal Sent BLM 7.6.4

89 RESEARCH PROPOSAL Name of Company: Employees: Feedback System: Environmental Concerns: Research/Support Design: BLM 7.6.5

90 Memo To: President and CEO of A Thermostat Incorporated From: Ministry of Energy and Control Date: September 12, 2010 Subject: Energy Conservation To Whom It May Concern: Ninety-five percent of the Canada's energy is collected via non-renewable resources (fossil fuels). The Ministry of Energy and Control believes that conservation is the key to sustainability. The government has spent 16 million dollars over the last two years on research and development. We have furthered our commitment to the development of a feedback system that optimizes the heating and cooling systems of our homes and buildings. Your company has been selected as one of just a few companies to present your research in this area. If chosen, your company will receive a 75 million dollar research grant. Your company will be required to present a proposal meeting the minimum expectations. Each company will be required to present a 5-minute proposal including the following highlights: 1. Describe steps that can be taken to conserve energy and explain the importance of doing so. 2. Describe the components of your system as it relates to the transfer of heat. 3. Explain how your company has used feedback systems in the past, and how successful were they. Give examples. 4. Discuss your company s unique approach to energy conservation and its impact on the environment (e.g., heat pollution both positive and negative aspects) We look forward to your presentation. Only those selected will be contacted. Selection will be based on the company s ability to meet all of the above criteria. BLM 7.6.6

91 The Lunch Box of the Future Due to the non-recyclable nature of expanded polystyrene and the ever growing demands on the environment, the nations of the world have decided to ban its commercial use. In response to this restriction, the Snack m Lunch Box Company is seeking design proposals for an expanded polystyrene free portable lunch container. This new improved lunch container will allow customers to pack taste pleasing lunches which include frozen treats, hot entrees, sandwiches and other room temperature selections. The company remains committed to providing high quality, environmentally friendly products to its many valued customers. Snack m has established a final selection process and will be evaluating your design using a rubric based on specific criteria. DESIGN CRITERIA The Lunch Box of the Future: 1. must not use expanded polystyrene in its construction 2. must not exceed a MAXIMUM dimension of 40 cm x 20 cm x 20 cm 3. must be divided into three sections (do not have to be equal) 4. must have a room temperature section which will hold a sandwich 5. must have a hot section which will hold a 500 ml container (margarine container) 6. must have a cold section which will hold a 500 ml container (margarine container) 7. can easily pack and unpack the food in each of the sections 8. must keep all of the sections at optimum temperatures so the food stays cold or hot or at room temperature 9. must be of high quality in terms of performance, construction, and appearance to ensure customer satisfaction TESTING CRITERIA TESTING TRIALS - complete at least three testing trials - date and record time length of trials - accurately measure and record the change in temperature in each section - accurately measure and record the temperature change in the hot liquid and the - - volume of melted liquid in the cold section - mathematically predict the results of the final testing day - modify the product based on trials to ensure the best possible results will be attained on final testing day BLM 7.7.1

92 FINAL TESTING - date and record length of final test - accurately measure and record, using an appropriate results table, the change in temperature in each section - accurately measure and record, using an appropriate results table, the temperature change of the hot liquid and the volume of melted liquid in the cold section - display the results of the temperature change of each section on one well-planned and completed graph - display the result of the temperature change of the hot liquid and the volume change of the melted liquid in an appropriate graph format PRESENTATION COMPONENTS WRITTEN PROPOSAL - cover page including title, presenters, and date - labelled sketch of product design - explanation of reasoning behind the placement of sections - explanation of reasoning behind the choice of materials - all testing data including tables and graphs for both trial tests and final test - explanation of modifications that were made based on trial test results - interpretation of results and how this relates to the overall effectiveness of the product - all journal entries highlight both the design and thinking processes used to develop the product including successes and difficulties - the main features of the product summarized and specific reasons given why the product should be chosen over all others - explanation of the process of heat transfer - the use of appropriate scientific vocabulary in written work ORAL PRESENTATION - well prepared and articulated sequence of information - detailed explanation of design process and reasoning behind choice of materials - detailed explanation of trial testing and how this impacted on the final design of the product - detailed explanation of final testing and how this demonstrates the product s overall effectiveness - key selling features of the product and its design components are highlighted - marketing effective and convincing - competent responses to questions related to the product - appropriate vocabulary used and an understanding of the scientific nature of heat demonstrated - support material used to enhance the presentation (models, graphs, media tools, etc.) - the attention of the audience held by using unique and creative presentation techniques BLM 7.7.1

93 TESTING TRIALS Create three charts the same as the one below and fill them in for each of the three trials. DATE LENGTH OF TIME ELAPSED INITIAL TEMPERATURE (degrees Celsius) FINAL TEMPERATURE (degrees Celsius) SECTION WITH HOT WATER SECTION WITH ICE SECTION WITH SANDWICH HOT WATER FINAL VOLUME OF LIQUID caused by melting in ml Reflect upon the following questions in your Science and Technology Journal. These will be submitted with final written proposal. 1. What does the trial test indicate about the effectiveness of the lunch box? 2. How successful was the trial? Why? 3. Do we need to change the materials we used for insulating? 4. What modifications are necessary to make the lunch box more efficient? 5. Based on the trial results, what will the temperature change be for each of the areas on the day of the Final Test? 6. Do we need to conduct more testing (e.g., more than the three assigned trial tests)? BLM 7.7.2

94 PROCESS CHECKLIST IS MY GROUP using our time wisely? 2. working cooperatively? 3. brainstorming ideas and making decisions based on sound scientific knowledge? 4. developing a plan and timeline for completion of assignment? 5. seeking feedback from peers? 6. seeking feedback from teacher? 7. checking off what we have completed? 8. making a to-do list? 9. completing reflective daily entries in our Science and Technology journal? 10. discussing and deciding on design options? 11. using and incorporating science vocabulary related to heat? 12. collecting all necessary equipment? 13. returning equipment when finished? 14. testing and modifying the product, based on knowledge of heat concepts? 15. checking the criteria to ensure we have completed all components of the project? 16. using the evaluation rubric to ensure that we are completing a high quality assignment 17. achieving our goals? BLM 7.7.3

95 LUNCH BOX RUBRIC CRITERIA LEVEL 1 LEVEL 2 LEVEL 3 LEVEL 4 Understanding the Lunch Box proposal and planning its design - demonstrates limited understanding of the problem - identifies and incorporates a few of predetermined criteria - plan demonstrates a limited understanding of the process of heat transfer - demonstrates a partial understanding of the problem - identifies and incorporates some of the predetermined criteria - plan demonstrates a partial understanding of the process of heat transfer - demonstrates a general understanding of the problem - identifies and incorporates most of the predetermined criteria - plan demonstrates a good understanding of the process of heat transfer - demonstrates a thorough understanding of the problem - identifies and incorporates all predetermined criteria - plan demonstrates a thorough understanding of the process of heat transfer Building the Lunch Box and performing testing - selects limited appropriate materials - makes a few modifications based on trial testing - records results with limited accuracy, following a few of the given criteria - selects appropriate materials - makes some modifications based on trial testing - records results that demonstrate some accuracy and follows some of the given criteria - selects appropriate materials to enhance performance - makes adequate modifications based on trial testing - records results that demonstrate general accuracy and follows most of the given criteria - selects appropriate materials and adapts it to enhance performance - makes necessary modifications based on trial testing and justifies choices - records accurate results that are detailed and relevant and follows all of the given criteria Interpreting results and how they relate to the Lunch Box - choice of materials and reasoning behind choices explained without justifications - interprets a few results and how they relate to the effectiveness of Lunch Box - result tables and graphs demonstrate limited accuracy and clarity - choice of materials and reasoning behind choices explained with some justifications - interprets some of the results and how they relate to the effectiveness of the Lunch Box - result tables and graphs demonstrate some accuracy and clarity - choice of materials and reasoning behind choices explained with general justifications - interprets most of the results and how they relate to the effectiveness of the Lunch Box - result tables and graphs demonstrate general accuracy and clarity - choice of materials and reasoning behind choices explained with justifications in detail - interprets the results and thoroughly relates them to the effectiveness of the Lunch Box - result tables and graphs demonstrate precision, accuracy and clarity and are well organized Presentation of the Lunch Box - identifies and explains a few factors that make their product marketable - written proposal including journal entries and oral presentation, including responses to questions, demonstrates limited clarity and supporting evidence - identifies and explains some factors that make their product marketable - written proposal including journal entries and oral presentation, including responses to questions, demonstrates some clarity and some supporting evidence of process is presented - identifies and explains most factors that make their product marketable - written proposal including journal entries and oral presentation, including responses to questions, demonstrates clarity and most of the supporting evidence of the process is presented - identifies and convincingly explains factors that make their product marketable - written proposal including journal entries and oral presentation, including responses to questions, demonstrates thoroughness and clarity with detailed supporting evidence of the process BLM 7.7.4

96 I.N.S.I.T.E. Method Throughout this unit students will be involved in inquiry based learning and investigations. The INSITE method, a problem solving model based on the principles of scientific inquiry, has been developed to help students conduct these investigations. Identify the problem Narrow the problem State the hypothesis Investigate and gather information Test your hypothesis and record observations Examine the results and write (communicate) conclusions Identify the problem In the first step students identify the problem they will investigate or need to resolve. Narrow the problem In the second step students narrow the problem. At this stage they will state the various questions (what, when, where, how, why, etc.) related to the problem. State the hypothesis In the third step students state the hypothesis. In this statement they will make a scientific guess as to what they believe will be a solution to the problem. Investigate and gather information In the fourth step students conduct a scientific investigation related to the hypothesis. Students will need to conduct research and gather information related to the problem and the questions they generated in the second step. Once students have enough background, they will create a plan of investigation to test their hypothesis. The students will need to consider all the possible variables and constants in order to carry out a fair test. Plans should include a list of materials they will need. Test the hypothesis and record observations In the fifth step students to follow their plan and carry out a fair test to confirm the validity of their hypothesis. Students will record their observations as they test their hypothesis. Students should be given opportunities to use a variety of recording devices such as charts, graphs, learning logs, or science journals. Examine the results and write (communicate) conclusions In the sixth step students examine the results of their test and then write a conclusion (communicate a response) that outlines what they learned in the investigation and testing of their hypothesis. It is important that students examine their results and whether or not their hypothesis was valid before writing their conclusion. If the hypothesis was not valid the students may need to either develop a new hypothesis or create a new plan to test the hypothesis in order to gain different results. Students should examine what worked and why, what needs further research, and what needs further investigation. If the hypothesis was valid the students should state the solution to the problem in their conclusion and outline why it was a solution. BLM 7.uw.1

97 I.N.S.I.T.E. Method I = Identify the problem N = Narrow the problem S = State the hypothesis I = Investigate and gather information T = Test the hypothesis and record observations E = Examine the results and write (communicate) conclusions BLM 7.uw.2