Across
1
Reddish electrical conductor
4
Unit of energy
6
Gas essential for breathing
7
Group of similar cells
11
Magnetic metallic element
12
Tectonic landmass section
15
Solid with repeating atomic pattern
Down
2
Naturally occurring inorganic solid
3
Compound containing oxygen
5
Unit of force
8
Nerve cell in the brain
9
Absolute temperature scale unit
10
Biological catalyst
13
Blocking of light by a celestial body
14
The Red Planet