Across
1
Substance with pH above 7
4
Gas form of a liquid
5
Unit of electric potential
6
Reddish electrical conductor
9
Gas essential for breathing
11
Positive particle in nucleus
Down
2
Path of a planet around the sun
3
Center of an atom or cell
5
Infectious microscopic agent
7
Amplified beam of light
8
Icy body with a tail near the sun
10
Our home planet