Across
1
Force that attracts objects together
3
Curved glass that refracts light
5
Smallest unit of an element
7
Measure of matter in an object
10
Center of an atom or cell
11
Solid with repeating atomic pattern
Down
2
Unit of electric potential
4
Glass that splits light into spectrum
6
The Red Planet
7
Natural satellite of Earth
8
Mass per unit volume
9
Ball of burning gas in space