Across
1
Gas form of a liquid
3
Group of similar cells
5
Curved glass that refracts light
7
Substance with pH below 7
9
Magnetic metallic element
10
Second lightest element
12
Naturally occurring inorganic solid
Down
2
Positive particle in nucleus
4
Molten rock beneath Earth surface
6
Disturbance that transfers energy
8
Compound containing oxygen
11
Push or pull on an object
13
Tissue that contracts for movement