Across
1
Compound containing oxygen
4
Amplified beam of light
6
Form of thermal energy
7
Unit of heredity
9
Tissue that contracts for movement
11
Particle of light
12
Push or pull on an object
Down
2
Positive particle in nucleus
3
Curved glass that refracts light
5
Chemical element in table salt
6
Second lightest element
8
The Red Planet
10
Mass per unit volume