Across
1
Biological catalyst
3
Substance with pH below 7
5
Precious yellow metallic element
8
Substance with pH above 7
9
Element found in all living things
Down
2
Compound containing oxygen
4
Solid with repeating atomic pattern
6
Tissue that contracts for movement
7
Gas form of a liquid
10
Smallest unit of an element
11
Positive particle in nucleus