Across
1
Force that attracts objects together
4
Reddish electrical conductor
6
Biological catalyst
8
Hottest planet in solar system
9
Precious yellow metallic element
10
Molten rock beneath Earth surface
Down
2
Chemical element in table salt
3
Substance with pH above 7
5
Icy body with a tail near the sun
7
Nerve cell in the brain
8
Unit of electric potential