Across
1
Mass per unit volume
4
Path of a planet around the sun
5
Gas form of a liquid
8
Glass that splits light into spectrum
10
Compound containing oxygen
11
Biological catalyst
12
Ball of burning gas in space
Down
2
Unit of energy
3
Unit of electric potential
5
Hottest planet in solar system
6
Measure of matter in an object
7
Our home planet
9
Solid with repeating atomic pattern