Across
1
Second lightest element
2
Smallest unit of an element
5
Magnetic metallic element
6
Biological catalyst
7
Curved glass that refracts light
8
Push or pull on an object
11
Hottest planet in solar system
Down
2
Substance with pH below 7
3
Icy body with a tail near the sun
4
Naturally occurring inorganic solid
9
Basic unit of life
10
Unit of heredity