Chapter 11 The Periodic Table Lesson 1 Using the Periodic Table Textbook pages 391 397 Lesson 2 Metals Textbook pages 401 402 Lesson 3 Nonmetals and Metalloids Textbook pages 409 410 & 413-414 1 Chapter 11 Lesson 1, 2 & 3 The Periodic Table Essential Questions: How are elements arranged on the periodic table? What can you learn about elements from the periodic table? What are the properties of metals, nonmetals, and metalloids? 2 1
What is the PERIODIC TABLE? The periodic table is a chart of the elements that is arranged into rows and columns according to the physical and chemical properties of the element. It shows all the known elements in the universe. It can be used to determine how all the elements are related to one another. 3 Developing a Periodic Table In 1869, a Russian chemist and teacher named Dmitri Mendeleev created a table to classify the elements. He arranged the elements in rows of increasing atomic mass. He grouped elements with similar properties in the same column. 4 2
Patterns in Properties The word periodic means repeating pattern. The days of the week are periodic because they repeat every seven days. Repeating patterns noticed by Mendeleev include: melting point, boiling point, and reactivity. Melting points increase and then decrease across a period. 5 Check Question What physical property did Mendeleev use to place the elements in rows on the periodic table? He used the physical property of atomic mass. 6 3
Predicting Properties of Undiscovered Elements After arranging the known elements of the time by increasing atomic mass, Mendeleev noticed large gaps between the elements. Mendeleev predicted that: scientists would discover new elements to fill in the gaps. the properties of the missing elements would be similar to the known elements in that column. His predictions were correct 7 Changes to Mendeleev s Table Mendeleev s tabled helped scientists relate the properties of elements to their position on the table. Mendeleev s table had one big problem: When arranged in order of increasing mass, some elements on the table seemed to be out of place. What could be done to fix the problem? 8 4
The Importance of the Atomic Number In the early 1900 s, scientist Henry Moseley solved the problem with Mendeleev s table. Instead of arranging the elements in order by increasing atomic mass, he arranged the elements in order by increasing atomic number. Atomic number is the number of protons in the nucleus of the atom. Now the elements in each column had similar properties. 9 Check Question What determines where an element is on the periodic table today? An element s atomic number determines the element s placement on the periodic table. 10 5
Today s Periodic Table The table is organized into columns called groups, rows called periods, and blocks based on certain patterns of properties. 11 What is on an element key? The key shows the element s name, atomic number, chemical symbol, and atomic mass. The key also shows the element s state of matter at room temperature. Element Name Atomic Number Chemical Symbol Atomic Mass Helium 2 He 4.00 State of Matter 12 6
Groups A group is a column on the periodic table. Elements in the same group have similar chemical properties. There are patterns in the physical properties of a group, such as density, melting point, and boiling point. The groups are numbered 1 18 at the top of each column on the periodic table. 13 2 Periods The rows on the periodic table are called periods. They are numbered from 1-7 The atomic number of each element increases by 1 as you read from left to right across each period. The physical and chemical properties of the elements also change as you move from left to right across a period. 14 7
Check Questions How is the periodic table organized? It has columns called groups, rows called periods, and blocks. What does the element key tell you about the element? The element key tells you the name of the element, the chemical symbol, the atomic number, the atomic mass, and the state at room temperature. 15 Which element is it? Use the periodic table to find the following elements: Atomic Number 6, 2, 20, 79, 26, 5, and 14 Then write down the element s Element name Chemical symbol Atomic mass State of matter Type of matter 16 8
Using Geometry The formula for determining the circumference of a circle is: C = d or C = 2 r Example: An iron atom (Fe) has a radius of 126 pm The circumference of an iron atom is: C = 2 x 3.14 x 126 C = 791 pm 17 Geometry Practice Find the circumference for the following atoms: Radius of uranium atom (U) is 156 pm Radius of nitrogen atom (N) is 75 pm Radius of arsenic atom (As) is 120 pm Radius of phosphorus atom (P)is 110 pm 18 9
Brain Pop Video The Periodic Table Of Elements http://www.brainpop.com/science/m atterandchemistry/periodictableofele ments/ 19 Metals, Nonmetals, & Metalloids Most of the elements on the periodic table are metals. Metals are on the left side and in the middle of the table. Metals can have different properties, but all metals are shiny and conduct electricity and thermal energy. 20 10
Metals, Nonmetals, & Metalloids Cont. Nonmetals, except hydrogen, are located on the right side of the periodic table. Nonmetals do not conduct electricity or thermal energy. Many nonmetals are gases. Carbon Between the metals and the nonmetals on the periodic table are the metalloids. Metalloids have properties of both metals and nonmetals. Silicon 21 Check Question Where are metals, nonmetals, and metalloids located on the periodic table? Metals are on the left side, nonmetals are on the right side except for hydrogen, and metalloids are between the metals and the nonmetals on the periodic table. 22 11
How Scientists Use the Periodic Table More than 100 elements are known today. Each element has its own unique set of properties. Elements that are near each other on the periodic table have similar properties. Scientists use the periodic table to understand and predict an elements properties. 23 Check Question How is the periodic table used to predict the properties of an element? The periodic table shows how elements and their properties relate to each other. Scientists use these patterns to predict the properties of new elements. 24 12
What is a Metal? Metals are some of the most useful elements. Forks, knives, copper wire, aluminum foil, gold jewelry, and many other things are made of metal. To be a metal, an element must have certain properties. 25 Physical Properties of Metals All metals share certain physical properties. A metal is an element that is generally shiny. It is easily pulled into wires or hammered into thin sheets. A metal is a good conductor of electricity and thermal energy. Luster is the ability of a metal to reflect light. Conductivity is the ability of a metal to carry an electric current or thermal energy. Ductility is the ability of a substance to be pulled into thin wires. Malleability is the ability of a substance to be hammered or rolled into sheets. 26 13
Other Physical Properties of Metals Metals have other physical properties. The density, strength, boiling point, and melting point of a metal are greater than those of other elements. Except for mercury, all metals are solid at room temperature. Many uses of a metal are determined by the metal s physical properties. 27 Check Question What are some physical properties of metals? The physical properties of metals include luster, malleability, ductility, conductivity, high densities, high melting points, and high boiling points. 28 14
Chemical Properties of Metals The chemical properties of metals differ greatly. Metals in the same group have similar chemical properties. Some metals are very or somewhat reactive and will easily react or combine with other elements. Some metals are nonreactive and therefore will not easily react or combine with other elements. 29 Patterns in Properties of Metals The properties of elements follow a repeating pattern across the periods. Elements increase in metallic properties such as luster, malleability, and conductivity as they move across the period from right to left. Elements also increase in metallic properties as they move down a group. 30 15
Nonmetals The Elements of Life Nonmetals are elements that have no metallic properties. More than 96 percent of the mass of your body comes from just four elements. These elements oxygen, carbon, hydrogen, and nitrogen are nonmetals. Of the remaining elements in your body, the two most common are also nonmetals phosphorus and sulfur. These 6 elements form the proteins, fats, carbohydrates and nucleic acids in your body and in other living things. 31 How Are Nonmetals Different From Metals? The properties of nonmetals are different from those of metals. Nonmetals do not conduct electricity or thermal energy well. For this reason they make good insulators. Nonmetals that are solid at room temperature have no luster. Many nonmetals are gases at room temperature. 32 16
Check Question What properties do nonmetals have? Most nonmetals are gases at room temperature. Solid nonmetals are dull, brittle, and poor conductors. 33 Metalloids A metalloid is an element that has physical and chemical properties of both metals and nonmetals. They are located between the metals and the nonmetals on the periodic table. The elements boron, silicon, germanium, arsenic, antimony, tellurium, polonium, and astatine are metalloids. Silicon is the most abundant metalloid in the universe and is found in sand, clay, rocks, and minerals 34 17
Check Question Where are metalloids located on the periodic table? Metalloids are located between the metals and the nonmetals. 35 Semiconductors A property of metalloids is the ability to act as a semiconductor. A semiconductor is an element that conducts electricity at high temperatures, but not at low temperatures. At high temperatures they act like metals and conduct electricity and at lower temperatures they act like nonmetals and do not conduct electricity. Useful property for electronic devices. 36 18
Properties and Uses of Metalloids Pure silicon is used in semiconductor devices for computers and other electronic products. Germanium is also used as a semiconductor. Boron is used in water softeners and laundry products. Boron also glows bright green in fireworks. 37 Metals, Nonmetals, & Metalloids You have learned that all metallic elements have common characteristics, such as malleability, conductivity, and ductility. Each metal also has unique properties that make it different from other metals. The same is true for nonmetals and metalloids. Knowing the properties of an element help you to understand how to use it. 38 19
Check Question How can the location of an element on the periodic table help provide information about it? The location of an element on the periodic table can help you learn the chemical and physical properties and understand how it can be used. 39 Brain Pop Video Metals, Nonmetals, & Metalloids http://www.brainpop.com/science/m atterandchemistry/metals/ 40 20