Across
1
Disturbance that transfers energy
3
Fourth state of matter
4
Tissue that contracts for movement
5
Smallest unit of an element
10
Gas essential for breathing
11
Unit of energy
12
Mass per unit volume
Down
2
Naturally occurring inorganic solid
3
Tectonic landmass section
6
Second lightest element
7
Unit of power
8
Ball of burning gas in space
9
Blocking of light by a celestial body