Across
1
Amplified beam of light
4
Naturally occurring inorganic solid
6
Gas form of a liquid
7
Icy body with a tail near the sun
8
Biological catalyst
11
Substance with pH below 7
Down
2
Substance with pH above 7
3
Unit of force
5
Path of a planet around the sun
6
Unit of electric potential
9
Precious yellow metallic element
10
Preserved remains of ancient life
12
Second lightest element