Across
1
Unit of electric potential
3
Icy body with a tail near the sun
4
Center of an atom or cell
5
Unit of energy
9
Force that attracts objects together
10
Substance with pH below 7
Down
1
Gas form of a liquid
2
Naturally occurring inorganic solid
6
The Red Planet
7
Substance with pH above 7
8
Hottest planet in solar system