Across
1
Particle of light
2
Unit of electric potential
4
Second lightest element
8
Gas form of a liquid
9
Substance with pH below 7
11
Natural satellite of Earth
Down
1
Fourth state of matter
2
Hottest planet in solar system
3
Precious yellow metallic element
5
Positive particle in nucleus
6
Glass that splits light into spectrum
7
Nerve cell in the brain
10
Basic unit of life