1. General, Organic, and Biological Chemistry Fourth Edition Karen Timberlake 3.2 The Periodic Table Chapter 3 Atoms and Elements © 2013 Pearson Education, Inc. Lectures

2. © 2013 Pearson Education, Inc. Chapter 3, Section 2 Periodic Table 2

3. © 2013 Pearson Education, Inc. Chapter 3, Section 2 Periods and Groups On the periodic table,  groups contain elements with similar properties and are arranged in vertical columns ordered from left to right.  periods are the horizontal rows of elements, and they are counted from the top as Period 1 to Period 7. 3

4. © 2013 Pearson Education, Inc. Chapter 3, Section 2 Periods and Groups 4

5. © 2013 Pearson Education, Inc. Chapter 3, Section 2 Group Numbers Group numbers use  numbers to identify the columns from left to right.  the letter A for the representative elements (1A to 8A) and the letter B for the transition elements. The representative elements include the first 2 groups, 1A (1) and 2A (2), in addition to groups 3A (13), 4A (14), 5A (15), 6A (16), 7A (17), and 8A (18). 5

6. © 2013 Pearson Education, Inc. Chapter 3, Section 2 Alkali Metals Group 1A (1), the alkali metals, includes lithium sodium, potassium, rubidium and cesium. The reactivity of these elements increases from the top to bottom of the group. 6

7. © 2013 Pearson Education, Inc. Chapter 3, Section 2 Halogens Group 7A (17), the halogens, includes fluorine, chlorine, bromine, iodine, and astatine. Fluorine and chlorine are highly reactive. 7

8. © 2013 Pearson Education, Inc. Chapter 3, Section 2 Nobel Gases Group 8A (18) is the nobel gases, which include helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe) and radon (Ra). Nobel gas elements are unreactive and are seldom found in combination with other elements. 8

9. © 2013 Pearson Education, Inc. Chapter 3, Section 2 Learning Check Identify the element described by the following: 1. Group 7A (17), Period 4 A. Br B. ClC. Mn 2. Group 2A (2), Period 3 A. beryllium B. magnesium C. boron 3. Group 5A (15), Period 2 A. phosphorus B. arsenic C. nitrogen 9

10. © 2013 Pearson Education, Inc. Chapter 3, Section 2 Solution Identify the element described by the following: 1. Group 7A (17), Period 4 A. Br 2. Group 2A (2), Period 3 B. magnesium 3. Group 5A (15), Period 2 C. nitrogen 10

11. © 2013 Pearson Education, Inc. Chapter 3, Section 2 Metals, Nonmetals, and Metalloids The heavy zigzag line separates metals and nonmetals.  Metals (blue) are located to the left.  Nonmetals (yellow) are located to the right.  Metalloids (green) are located along the heavy zigzag line between the metals and nonmetals. 11

12. © 2013 Pearson Education, Inc. Chapter 3, Section 2 Properties of Metals, Nonmetals, and Metalloids Metals are  shiny and ductile.  good conductors of heat and electricity. Nonmetals are  not especially shiny, ductile, or malleable.  poor conductors of heat and electricity. Metalloids are  better conductors than nonmetals, but not as good as metals.  used as semiconductors and insulators. 12

13. © 2013 Pearson Education, Inc. Chapter 3, Section 2 Comparing a Metal, a Metalloid, and a Nonmetal 13

14. © 2013 Pearson Education, Inc. Chapter 3, Section 2 Major Elements Essential to Health Amounts of essential elements in a 60-kg adult: 14

15. © 2013 Pearson Education, Inc. Chapter 3, Section 2 Learning Check Identify each of the following elements as a metal, a nonmetal, or a metalloid. 1. sodium____ 2. chlorine____ 3. silicon ____ 4. iron____ 5. carbon____ 15

16. © 2013 Pearson Education, Inc. Chapter 3, Section 2 Solution Identify each of the following elements as a metal, a nonmetal, or a metalloid. 1. sodium____metal 2. chlorine____nonmetal 3. silicon ____metalloid 4. iron____metal 5. carbon____nonmetal 16

17. © 2013 Pearson Education, Inc. Chapter 3, Section 2 Learning Check Match the elements to the description. 1. Metals in Group 4A (14) A. Sn, Pb B. C, Si C. C, Si, Ge, Sn 2. Nonmetals in Group 5A (15) A. As, Sb, Bi B. N, P C. N, P, As, Sb 3. Metalloids in Group 4A (14) A. C, Si, Ge, B. Si, Ge C. Si, Ge, Sn, Pb 17

18. © 2013 Pearson Education, Inc. Chapter 3, Section 2 Solution Match the elements to the description. 1. Metals in Group 4A (14) A. Sn, Pb 2. Nonmetals in Group 5A (15) B. N, P 3. Metalloids in Group 4A (14) B. Si, Ge 18