Across
1
Unit of electric potential
4
Fourth state of matter
6
Path of a planet around the sun
7
Chemical element in table salt
8
Curved glass that refracts light
11
Glass that splits light into spectrum
12
Push or pull on an object
Down
2
Preserved remains of ancient life
3
Positive particle in nucleus
5
Smallest unit of an element
9
The Red Planet
10
Icy body with a tail near the sun