Across
1
Hottest planet in solar system
2
Tectonic landmass section
4
Element found in all living things
7
Smallest unit of an element
8
Compound containing oxygen
10
Molten rock beneath Earth surface
Down
2
Fourth state of matter
3
Basic unit of life
4
Reddish electrical conductor
5
Group of similar cells
6
Gas essential for breathing
9
Unit of electric potential