Across
1
Gas essential for breathing
5
Basic unit of life
6
Push or pull on an object
8
Blocking of light by a celestial body
9
Hottest planet in solar system
11
Precious yellow metallic element
Down
2
Unit of energy
3
Disturbance that transfers energy
4
Biological catalyst
7
Second lightest element
9
Unit of electric potential
10
Reddish electrical conductor
12
Element found in all living things