Across
1
Naturally occurring inorganic solid
2
Glass that splits light into spectrum
4
Unit of force
7
Form of thermal energy
8
Particle of light
11
Nerve cell in the brain
13
Smallest unit of an element
Down
2
Positive particle in nucleus
3
Curved glass that refracts light
5
Force that attracts objects together
6
Icy body with a tail near the sun
9
Tissue that contracts for movement
10
Element found in all living things
12
Magnetic metallic element