Across
1
Substance with pH below 7
3
Center of an atom or cell
5
The Red Planet
6
Ball of burning gas in space
9
Unit of power
10
Unit of electric potential
Down
2
Infectious microscopic agent
4
Form of thermal energy
5
Measure of matter in an object
7
Unit of force
8
Magnetic metallic element
11
Gas form of a liquid
