Across
1
Gas form of a liquid
3
Chemical element in table salt
4
Biological catalyst
7
Compound containing oxygen
9
Substance with pH below 7
10
Smallest unit of an element
11
Blocking of light by a celestial body
Down
2
Disturbance that transfers energy
3
Ball of burning gas in space
5
Unit of heredity
6
Tectonic landmass section
7
Gas essential for breathing
8
Naturally occurring inorganic solid