Across
1
Disturbance that transfers energy
4
Smallest unit of an element
6
Reddish electrical conductor
8
Biological catalyst
10
Force that attracts objects together
12
Compound containing oxygen
Down
2
Infectious microscopic agent
3
Molten rock beneath Earth surface
5
Push or pull on an object
7
Icy body with a tail near the sun
9
Tectonic landmass section
11
Mass per unit volume