Across
1
Positive particle in nucleus
4
Particle of light
5
Measure of matter in an object
7
Mass per unit volume
8
Element found in all living things
10
Blocking of light by a celestial body
11
Substance with pH below 7
Down
2
Force that attracts objects together
3
Push or pull on an object
4
Glass that splits light into spectrum
6
Center of an atom or cell
9
Tectonic landmass section