Across
1
Amplified beam of light
3
Particle of light
6
Solid with repeating atomic pattern
7
Unit of electric potential
9
Preserved remains of ancient life
12
Chemical element in table salt
13
Compound containing oxygen
Down
2
Group of similar cells
4
Second lightest element
5
Gas essential for breathing
8
Fourth state of matter
10
Form of thermal energy
11
Mass per unit volume
14
Unit of energy