Across
1
Blocking of light by a celestial body
5
Particle of light
8
Smallest unit of an element
10
Substance with pH below 7
11
Mass per unit volume
Down
2
Compound containing oxygen
3
Path of a planet around the sun
4
Substance with pH above 7
5
Tectonic landmass section
6
Chemical element in table salt
7
Positive particle in nucleus
9
Solid with repeating atomic pattern