Across
1
Absolute temperature scale unit
3
Positive particle in nucleus
4
Substance with pH above 7
7
Path of a planet around the sun
9
Naturally occurring inorganic solid
10
Center of an atom or cell
12
Substance with pH below 7
Down
2
Solid with repeating atomic pattern
3
Particle of light
5
Unit of force
6
Curved glass that refracts light
8
Unit of electric potential
11
Compound containing oxygen