Across
1
Center of an atom or cell
6
Gas form of a liquid
7
Blocking of light by a celestial body
8
Precious yellow metallic element
9
Biological catalyst
Down
2
Positive particle in nucleus
3
Element found in all living things
4
Hottest planet in solar system
5
Solid with repeating atomic pattern
10
Disturbance that transfers energy
11
Unit of force
12
Second lightest element
13
Unit of heredity