Across
1
Naturally occurring inorganic solid
4
Mass per unit volume
9
Substance with pH above 7
10
Smallest unit of an element
11
Particle of light
13
Tissue that contracts for movement
Down
2
Icy body with a tail near the sun
3
Absolute temperature scale unit
5
Unit of energy
6
Reddish electrical conductor
7
Ball of burning gas in space
8
Basic unit of life
12
Compound containing oxygen