Across
1
Smallest unit of an element
2
Blocking of light by a celestial body
4
Substance with pH above 7
5
Preserved remains of ancient life
7
Precious yellow metallic element
Down
2
Biological catalyst
3
Naturally occurring inorganic solid
6
Substance with pH below 7
8
Particle of light
9
Solid with repeating atomic pattern
10
Tectonic landmass section