1

Chapter 4 Atoms and Elements

4.2

The Periodic Table

Basic Chemistry Copyright © 2011 Pearson Education, Inc.

Lithium, sodium, and potassium are three elements in the alkali metal family, Group 1A (1).

2

Groups and Periods

On the periodic table

• elements are arranged according to similar properties

• groups contain elements with similar properties in vertical columns

• periods are horizontal rows of elements

Basic Chemistry Copyright © 2011 Pearson Education, Inc.

3

Groups and Periods

Basic Chemistry Copyright © 2011 Pearson Education, Inc.

On the periodic table, each vertical column represents a group of elements, and each horizontal row of elements represents a period.

4

Periodic Table

Basic Chemistry Copyright © 2011 Pearson Education, Inc.

Groups and periods on the periodic table.

5

Group Numbers

Group Numbers

• use the letter A for the representative elements 1A to 8A and the letter B for the transition elements

• also use numbers 1-18 for the columns from left to right

Basic Chemistry Copyright © 2011 Pearson Education, Inc.

6

Names of Some Representative Elements

• Several groups of representative elements are known by common names.

Basic Chemistry Copyright © 2011 Pearson Education, Inc.

7

Alkali MetalsGroup 1A (1), the alkali metals, includes lithium, sodium, and potassium.

Basic Chemistry Copyright © 2011 Pearson Education, Inc.

Lithium, sodium, and potassium are three elements in the alkali metal family, Group 1A (1).

8

Halogens

Group 7A (17) thehalogens, includes• chlorine • bromine• iodine

Basic Chemistry Copyright © 2011 Pearson Education, Inc.

Chlorine, bromine, and iodine are three halogens from Group 7A (17).

9

Identify the element described by the following:A. Group 7A (17), Period 4

1) Br 2) Cl 3) Mn

B. Group 2A (2), Period 3 1) beryllium 2) magnesium 3) boron

C. Group 5A (15), Period 2 1) phosphorus 2) arsenic 3)

nitrogen

Learning Check

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10

A. Group 7A (17), Period 4 1) Br

B. Group 2A (2), Period 3

2) magnesium

C. Group 5A (15), Period 2

3) nitrogen

Solution

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11

Metals, Nonmetals, and MetalloidsThe heavy zigzag line on the periodic table

separates metals and nonmetals.• Metals are located to the left• Nonmetals are located to the right • Metalloids are located along the heavy zigzag

line between the metals and nonmetals

Basic Chemistry Copyright © 2011 Pearson Education, Inc.

12

Metals • are shiny and ductile• are good conductors of heat and electricity

Nonmetals• are dull, brittle, and poor conductors• are good insulators

Metalloids• are better conductors than nonmetals, but not

as good as metals• are used as semiconductors and insulators

Properties of Metals, Nonmetals, and Metalloids

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13

Comparing A Metal, Metalloid, and Nonmetal

Basic Chemistry Copyright © 2011 Pearson Education, Inc.

14

Identify each of the following elements as

1) metal 2) nonmetal 3) metalloid

A. sodium ____

B. chlorine ____

C. silicon ____

D. iron ____

E. carbon ____

Learning Check

Basic Chemistry Copyright © 2011 Pearson Education, Inc.

15

Identify each of the following elements as

1) metal 2) nonmetal 3) metalloid

A. sodium 1) metal

B. chlorine 2) nonmetal

C. silicon 3) metalloid

D. iron 1) metal

E. carbon 2) nonmetal

Solution

Basic Chemistry Copyright © 2011 Pearson Education, Inc.

16

Match the elements to the description:

A. Metals in Group 4A (14) 1) Sn, Pb 2) C, Si 3) C, Si, Ge, Sn

B. Nonmetals in Group 5A (15) 1) As, Sb, Bi 2) N, P 3) N, P, As, Sb

C. Metalloids in Group 4A (14) 1) C, Si, Ge, 2) Si, Ge 3) Si, Ge, Sn, Pb

Learning Check

Basic Chemistry Copyright © 2011 Pearson Education, Inc.

17

Match the elements to the description:A. Metals in Group 4A (14)

1) Sn, Pb

B. Nonmetals in Group 5A (15) 2) N, P

C. Metalloids in Group 4A (14) 2) Si, Ge

Solution

Basic Chemistry Copyright © 2011 Pearson Education, Inc.