Across
1
Naturally occurring inorganic solid
4
Gas essential for breathing
5
Substance with pH above 7
6
Magnetic metallic element
12
Basic unit of life
Down
2
Ball of burning gas in space
3
Nerve cell in the brain
7
Substance with pH below 7
8
Icy body with a tail near the sun
9
Absolute temperature scale unit
10
Unit of electric potential
11
Tectonic landmass section