Across
1
Amplified beam of light
4
Infectious microscopic agent
6
Substance with pH below 7
7
Unit of heredity
8
Magnetic metallic element
9
Substance with pH above 7
11
Force that attracts objects together
Down
2
Chemical element in table salt
3
Ball of burning gas in space
5
Unit of energy
10
Form of thermal energy
12
Hottest planet in solar system