Across
1
Chemical element in table salt
3
Unit of power
5
Magnetic metallic element
8
Infectious microscopic agent
9
Measure of matter in an object
Down
1
Ball of burning gas in space
2
Molten rock beneath Earth surface
3
Disturbance that transfers energy
4
Force that attracts objects together
6
Center of an atom or cell
7
Mass per unit volume
