Across
1
Compound containing oxygen
5
Gas essential for breathing
7
Hottest planet in solar system
8
Element found in all living things
10
Glass that splits light into spectrum
11
Tectonic landmass section
12
Mass per unit volume
Down
2
Smallest unit of an element
3
Our home planet
4
Magnetic metallic element
6
Unit of heredity
9
Amplified beam of light