Across
1
Infectious microscopic agent
3
Unit of heredity
7
Precious yellow metallic element
8
Substance with pH below 7
9
Blocking of light by a celestial body
11
Particle of light
Down
2
Disturbance that transfers energy
4
Reddish electrical conductor
5
Chemical element in table salt
6
Absolute temperature scale unit
10
Second lightest element
12
Unit of electric potential