Across
1
Molten rock beneath Earth surface
4
Mass per unit volume
6
Compound containing oxygen
7
Fourth state of matter
8
Ball of burning gas in space
9
Tectonic landmass section
11
Center of an atom or cell
Down
2
Biological catalyst
3
Smallest unit of an element
5
Chemical element in table salt
7
Particle of light
10
Curved glass that refracts light