Chapter 3

1. A helium-neon laser emits light at 633 nm. What color is this light?

2. Complete the following table:

Name of Element Symbol Atomic # Mass # # of Protons # of Neutrons # of Electrons
  N   14      
Calcium     40      
        38 50  
    14     14  
    56 137      

3. What are the elements that contain each of the following numbers of protons? Give their names and chemical symbols.

a. 1

b. 76

c. 29

d. 21

e. 95

4. Sort the following forms of electromagnetic radiation in order of increasing energy:

a. infrared light

b. AM radio waves

c. FM radio waves

d. blue light

5. What happens when an electron collapses back to its ground state from an excited state?

6. Draw a diagram similar to Table 3.2 with the electronic configuration of the following elements:

a. sodium

b. magnesium

c. aluminum

d. silicon

e. phosphorus

f. argon

7. How many valence electrons does each element in Question #6. have?

8. Classify each of the following as a solid, liquid or gas at room temperature.

a. mercury

b. helium

c. oxygen

d. gold

9. Classify each of the following elements as a metal or a nonmetal.

a. helium

b. sodium

c. iodine.

d. calcium

c. boron