Across
1
Magnetic metallic element
3
Particle of light
4
Force that attracts objects together
7
Naturally occurring inorganic solid
8
Substance with pH above 7
11
Icy body with a tail near the sun
Down
2
Unit of electric potential
3
Glass that splits light into spectrum
5
Unit of force
6
Ball of burning gas in space
9
Center of an atom or cell
10
Nerve cell in the brain