Title: Feb 14 11:20 AM (1 of 58)

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1 Title: Feb 14 11:20 AM (1 of 58)

2 Introduction to Chemistry What is chemistry? Title: Feb 12 6:47 PM (2 of 58)

3 Title: Dec 3 11:24 AM (3 of 58)

4 Introduction to Chemistry What is chemistry? Definition: The study of matter, its structure and properties, and how it changes during chemical reactions. Properties of Matter: Characteristics of a material that allow you to identify it. Title: Feb 12 6:47 PM (4 of 58)

5 Defining Matter What is matter? Give me some examples of things you would call matter. Can you give examples of things that are not matter? Title: Feb 12 6:47 PM (5 of 58)

6 Defining Matter Matter can be defined as anything that has both mass and volume. Mass is similar to (but not the same as) weight*; volume simply means tha matter takes up space. *Another way to define mass is "resistance to change in motion". This eliminates the problem of objects which don't have weight (for example, in space); they will still have mass, and still resist changing their motion in proportion to their mass. Title: Feb 12 6:47 PM (6 of 58)

7 Classifying Matter We can break all matter into two major categories 1) Pure Substances 2) Mixtures Title: Feb 12 6:47 PM (7 of 58)

8 Classifying Matter Pure Substances include Elements and compounds. These materials have a uniform and fixed composition. Uniform all parts of the substance are the same Fixed the ratio of elements within the material is not variable Title: Feb 12 6:47 PM (8 of 58)

9 Particles of Matter We say that all matter is composed of "small particles". What do we call the smallest particles of matter? We define atoms as the simplest particles of matter whichretain their properties. The last part is important...atoms are not the absolute smallest particles of matter, but a single atom still has all the same properties as the material it's made of... if it is broken down any further, those properties are lost. Title: Feb 12 6:47 PM (9 of 58)

10 Title: Dec 4 8:10 AM (10 of 58)

11 Atoms What do we call a material composed entirely of a single type of atom? Examples of elements: Title: Feb 12 6:47 PM (11 of 58)

12 Classifying Matter Elements Substances composed entirely of a single type of atom All of the elements are listed in the Periodic Table. Examples: oxygen, iron, helium, neon, sodium Title: Feb 12 6:47 PM (12 of 58)

13 Periodic Table All of the elements are listed in the periodic table. There are about 120 known elements, although many of these are very uncommon, and some do not occur naturally. There is a great variety of properties among the elements. Most are solid at room temperature, some are a gas at room temperature, and only two (Bromine and Mercury) are liquid at room temperature. The elements can be divided into groups based on their properties. Title: Feb 12 6:47 PM (13 of 58)

14 1 H Hydrogen 3 4 Li Be Lithium Beryllium Periodic Table of the Elements Each element on the periodic table has a name and a symbol B C N O F 2 He Helium Ne Boron Carbon Nitrogen Oxygen Fluorine Neon Na K Mg Sodium Magnesium Ca Potassium Calcium The symbol can be a single capital letter, or a capital and lowercase letter Sc Scandium Ti Titanium V Vanadium Cr Chromium Mn Manganese Fe Co Ni Cu Zn Iron Cobalt Nickel Copper Zinc Al Ga Si Ge P As Cl Br Ar Aluminium Silicon Phosphorus Sulfur Chlorine Argon S Se Kr Gallium Germanium Arsenic Selenium Bromine Krypton Rb Sr Rubidium Strontium Y Zr Nb Mo Tc Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Ru Rh Pd Ag Cd In Sn Sb Te I Xe Indium Tin Antimony Tellurium Iodine Xenon Cs Ba Cesium Barium La Hf Ta W Re Lanthanum Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury Os Ir Pt Au Hg Tl Pb Bi Po At Rn Thallium Lead Bismuth Polonium Astatine Radon Fr Ra Francium Radium Ac Rf Db Sg Bh Hs Mt Actinium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium The symbols are usually related to the element's name, but not always Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Cf Th Pa U Np Pu Am Cm Bk Es Fm Md No Lr Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Title: Periodic table (14 of 58)

15 Layout of the Periodic Table Why is the table arranged the way it is? Why is there that separate group down at the bottom? Look at the gap between and The separate group, called the Rare Earth Metals, fits in between these elements. They are separated out from the others so that the table fits easily on a page! Otherwise, the table would be VERY long and thin...like this... Title: Feb 12 6:47 PM (15 of 58)

16 Classifying Matter Compounds Substances composed of two or more types of atoms, in a fixed ratio. A compound formula shows the rationin which the elements of a compound are fixed. Examples: H2O (two hydrogen for every one oxygen) C6H12O6 (6 carbon; 12 hydrogen; 6 oxygen) Fe(NO3)2 (1 iron; 2 nitrogen; 6 oxygen) Title: Feb 12 6:47 PM (16 of 58)

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18 Compounds When two or more elements combine in a chemical reaction, they form a compound. The atoms of each element join together, combining in a fixed ratio. Two elements may combine in more than one ratio, but the resulting compounds will be different, and will have different properties. There are many more compounds in the world than elements: Title: Feb 12 6:47 PM (18 of 58)

19 Compounds Why do you think there can be so many more compounds than elements? Think of this: Why are there more words than there are letters? Title: Feb 12 6:47 PM (19 of 58)

20 Pure Substances Atoms and compounds are called pure substances, because they are composed entirely of the same type of atoms, or of atoms combined in a fixed ratio. In other words, all samples of a pure substance will be the same. What would the particles look like in an element? What would the particles look like in an compound? Title: Feb 12 6:47 PM (20 of 58)

21 Mixtures A mixture is two or more elements or compounds There are even more mixtures than there are compounds. Not all elements will combine in a chemical reaction to form a compound, but any two (or more) elements or compounds can be tossed together to make a mixture. What are some examples of mixtures? Title: Feb 12 6:47 PM (21 of 58)

22 Mixtures Mixtures do not have a fixed composition. They may be classified as either solutions or heterogeneous mixtures. Solutions Composition is uniform, but variable. All the particles are spread out evenly, and all parts of the solution will appear the same. Solutions will still usually be transparent.* *Solutions may have color, but you can still see that light passes through them. Heterogeneous mixtures comosition is both variable and not uniform; there are at least two "phases" in the mixture; in other words, there are visible differences in different parts of the mixture. Title: Feb 12 6:47 PM (22 of 58)

23 Mixtures Classify the examples as solutions or heterogeneous mixtures: Title: Feb 12 6:47 PM (23 of 58)

24 Drawing Mixtures Remember what the particles in elements and compounds looked like? What would the particles in a mixture look like? Title: Feb 12 6:47 PM (24 of 58)

25 Homework: Pure Substances and Mixtures Matter Title: Feb 12 6:47 PM (25 of 58)

26 Review Homework Read the Introduction to Chapter 5, and Section 5.1 (pages in your text.) Complete Questions #1 5 on page 175 Title: Feb 12 6:47 PM (26 of 58)

27 Review Homework 1. Classify each of the following as a pure substance or a mixture. Explain your choices. (a) Soapy water (b) Hydrogen gas (c) Sodium chloride Title: Feb 12 6:47 PM (27 of 58)

28 Review Homework 2. Classify each of the following as an element or a compound. Explain your choices. (a) Hydrogen (b) Potassium carbonate (c) Water (d) Mg Title: Feb 12 6:47 PM (28 of 58)

29 Review Homework 3. Draw sketches to represent 10 particles of the following: (a) (b) (c) Element Compound Mixture *These were already done during class notes Title: Feb 12 6:47 PM (29 of 58)

30 Review Homework 4. Classify each of the following as a physical property or a chemical property. Explain your choices. (a) Gasoline is a clear, pink solution (b) Gasoline burns in air (c) Water boils at 100 C (d) Electric current can split water into hydrogen and oxygen gases. Title: Feb 12 6:47 PM (30 of 58)

31 Review Homework 5. When aluminum metal is addes to hydrobromic acid, hydrogen gas and an aluminum bromide solution are formed. (a) What kind of change has occurred? Explain. (b) Which substances are the reactants, and which are the products? Title: Feb 12 6:47 PM (31 of 58)

32 Question 6 from page In your own words, describe the chemical tests that can be used to identify the following gases: (a) Hydrogen (b) Oxygen (d) Water vapor (c) Carbon dioxide (demo) Title: Feb 12 6:47 PM (32 of 58)

33 Title: Dec 4 11:46 AM (33 of 58)

34 Properties of Matter What is meant by a property of a substance? What are some examples of properties of matter? Title: Feb 12 6:47 PM (34 of 58)

35 Properties of Matter Two types of properties: Physical Chemical Title: Feb 12 6:47 PM (35 of 58)

36 States of Matter What are the three states of matter? Describe the properties you could use to identify each state. Solid: fixed shape and volume (solids maintain their shape, and are non compressible Liquid: variable shape, but fixed volume (liquids take the shape of their container, from the bottom up, but are still non compressible Gas: variable shape and volume (gases take the shape of their container, and they are compressible...they expand to fill their container, but can be squeezed into smaller volumes when pressure is applied) Title: Feb 12 6:47 PM (36 of 58)

37 Changes of State Two useful properties of a material are its melting and boiling points. These are the temperatures at which the material changes state, going from a solid to a liquid (melting), or from a liquid to a gas (boiling...slower transition from liquid to a gas is called vaporization or evaporation.) Title: Feb 12 6:47 PM (37 of 58)

38 Changes of State These changes can also happen in reverse: A change from a gas to a liquid is called condensation A change from a solid to a liquid is called solidification or freezing It is also possible for a material to change from a solid to a gas, or gas to solid, directly, without ever becoming a liquid in between. This is called sublimation. Can you think of some examples of this happening? Title: Feb 12 6:47 PM (38 of 58)

39 Metals and Nonmetals Two major groups of elements are the metals and the nonmetals. Look at the examples below. Which ones are metals? Nonmetals? How can you tell? Title: Feb 12 6:47 PM (39 of 58)

40 1 H Hydrogen 3 4 Li Na K Rb Be Lithium Beryllium Mg Sodium Magnesium Ca Potassium Calcium Sr Rubidium Strontium Sc Scandium Y Yttrium Ti Titanium Zr Zirconium Periodic Table of the Elements Most of the elements are metals. They are listed on the left side of the table. Nonmetals are on the right side. The far right are a special group called the inert gases, or noble gases V Vanadium Nb Niobium Cr Chromium Mo Molybdenum Mn Manganese Tc Technetium Fe Ru Ruthenium Co Rh Rhodium Ni Pd Cu Ag Zn Iron Cobalt Nickel Copper Zinc Cd Palladium Silver Cadmium B Al Ga In C Si Ge Sn N P As Sb O Aluminium Silicon Phosphorus S Sulfur Se Te F Cl Chlorine Br I 2 He Helium Ne Boron Carbon Nitrogen Oxygen Fluorine Neon Ar Argon Kr Gallium Germanium Arsenic Selenium Bromine Krypton Xe Indium Tin Antimony Tellurium Iodine Xenon Cs Ba Cesium Barium La Hf Ta W Re Lanthanum Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury Os Ir Pt Au Hg Tl Pb Bi Po At Rn Thallium Lead Bismuth Polonium Astatine Radon Fr Ra Francium Radium Ac Rf Db Sg Bh Hs Mt Actinium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium The noble gases are special nonmetals that are very unreactive...in other words, they almost never react with other elements Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Cf Th Pa U Np Pu Am Cm Bk Es Fm Md No Lr Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Title: Periodic table (40 of 58)

41 Atomic Structure What do you already know about the structure of atoms? (Brainstorm) LokenTimer2.swf Title: Feb 12 6:47 PM (41 of 58)

42 Parts of an Atom There are two main areas in an atom. The center of the atom, where almost all of the mass is located, is the nucleus. The nucleus is surrounded by an electron cloud. Nucleus Electron cloud Title: Feb 12 6:47 PM (42 of 58)

43 Parts of an Atom We said that, even though an atom is the smallest particle which keeps its properties, it is not the smallest particle of matter possible. Atoms are made up of three smaller particles. What are they? Title: Feb 12 6:47 PM (43 of 58)

44 Parts of an Atom What do you already know about protons, neutrons, and electrons? See if you can fill in the following chart: Particle > Proton Neutron Electron Location > Electric Charge > Relative Size (AMU) > Title: Feb 12 6:47 PM (44 of 58)

45 Atomic Structure Every element is made up entirely of atoms with a specific number of protons, neutrons, and electrons. All of the atoms of any element will have the same structure. We'll look in more detail at atomic structure later. Title: Feb 12 6:47 PM (45 of 58)

46 Atomic Structure Turn to the periodic table in the back of your book. Every element is made up entirely of atoms with a specific number of protons, neutrons, and electrons. All of the atoms of any element will have the same structure...in other words, the same number of protons, neutrons*, and electrons. *Actually, the number of neutrons can vary slightly even among atoms of the same element...we'll cover that shortly. Title: Feb 12 6:47 PM (46 of 58)

47 Reading the Periodic Table Atomic number Symbol 17 Cl Element name Chlorine Relative atomic mass Title: Feb 12 6:47 PM (47 of 58)

48 Reading the Periodic Table Atomic number The number of protons in the nucleus. This number will not change for any element. (If there is a different number of protons, it isn't the same element anymore!) Electrons The number of electrons will be the same as the number of protons. Why is this? Title: Feb 12 6:47 PM (48 of 58)

49 Reading the Periodic Table Relative Atomic Mass The atomic mass is the average mass for an atom of the element listed. Not all atoms of the same element have identical atomic mass. Why? What do we call atoms of the same element with different atomic mass? Title: Feb 12 6:47 PM (49 of 58)

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51 Homework Atomic Structure Fill in atomic structures, similar to what we just did during class, for the following elements: Hydrogen Nitrogen Sodium Beryllium Chlorine Calcium Iron Copper Bromine Argon Oxygen Helium Title: Feb 12 6:47 PM (51 of 58)

52 Chemical Changes Chemical changes are what happens to matter during a chemical reaction. (In other words...they are what you see when observing a chemical property) Chemical changes are different from physical changes in a couple of very important ways: *During a chemical change, a new material is formed (for example, when you burn wood in a fireplace, you produce smoke and ashes) *Chemical changes are usually not reversible (you can't un burn the piece of wood. Title: Feb 12 6:47 PM (52 of 58)

53 Chemical Changes There are five main signs you look for that tell you a chemical reaction has happened between two materials: 1) There is a color change 2) A solid has formed from mixing two liquids (this is called a precipitate) 3) Bubbles are formed, without adding heat 4) There is a change in energy (heat is produced or absorbed, light is given off) 5) There is a change in smell (an odor given off) Title: Feb 12 6:47 PM (53 of 58)

54 Chemical Reactions Demonstration Create a chart like the one shown below to record your observations for each of the chemical reactions that are demonstrated: Observations before reaction: Observations during/after reaction: Signs that a chemical reaction has ocurred: Title: Feb 12 6:47 PM (54 of 58)

55 Chemical Reactions Demonstration Reaction 1: Silver nitrate solution and Sodium chloride solution Reaction 2: Iron and copper (II) sulfate solution Reaction 3: Copper (II) nitrate solution and potassium iodide solution Reaction 4: Hydrochloric acid and zinc metal (use a lit wooden splint to identify the gas)* Reaction 5: Silver nitrate solution and Sodium iodide solution Reaction 6: Magnesium metal and oxygen (combustion)* Reaction 7: Iron (III) nitrate and potassium thiocyanate Reaction 8: Silver nitrate and potassium dichromate Reaction 9: Copper (II) chloride solution and Sodium hydroxide solution Reaction 10: Barium hydroxide and ammonium thiocyanate (solids)* *What is the difference between an endothermic reaction and an exothermic reaction? Title: Feb 12 6:47 PM (55 of 58)

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