Across
1
Solid with repeating atomic pattern
5
Our home planet
6
Amplified beam of light
10
Fourth state of matter
12
Substance with pH below 7
13
Mass per unit volume
Down
2
Disturbance that transfers energy
3
Tissue that contracts for movement
4
Substance with pH above 7
7
Force that attracts objects together
8
Unit of power
9
Particle of light
11
Naturally occurring inorganic solid