Across
1
Substance with pH above 7
3
Curved glass that refracts light
5
Center of an atom or cell
7
Solid with repeating atomic pattern
9
Icy body with a tail near the sun
10
Naturally occurring inorganic solid
11
Ball of burning gas in space
Down
2
Mass per unit volume
4
Blocking of light by a celestial body
6
Measure of matter in an object
8
Substance with pH below 7