Across
1
Biological catalyst
3
Gas form of a liquid
4
Unit of electric potential
6
Ball of burning gas in space
7
Element found in all living things
9
Substance with pH above 7
10
The Red Planet
Down
2
Amplified beam of light
3
Hottest planet in solar system
5
Path of a planet around the sun
8
Gas essential for breathing
11
Disturbance that transfers energy