• San Diego Mesa College

• CHEMISTRY 152

Chemistry 152 Homework 7 key

1. Write the modern periodic law. The properties of the elements are a periodic function of atomic

number

2. Why do elements in the same group have similar properties? They have similar configurations

3. For each of the atoms below, indicate if it is a metal, nonmetal or metalloid:

a. C nonmetal

b. Cd metal

c. S nonmetal

d. Zn metal

e. Sc metal

4. For each pair of atoms, indicate which has the larger radius. (blue)

a. N, F

b. O, S

c. Cs, Cl

5. Define the following terms:

a. ionization energy energy required to remove an electron

b. electronegativity relative attraction for electrons when bound to another atom

6. For each parameter below, tell how it varies across a row and down a group.

Across down

a. ionization energy increase decrease

b. attraction for electrons increase decrease

c. electronegativity increase decrease

For problems 7 - 9, consider the following pairs of atoms: