Across
1
Particle of light
4
Substance with pH above 7
6
Solid with repeating atomic pattern
7
Reddish electrical conductor
8
Mass per unit volume
10
Form of thermal energy
12
Chemical element in table salt
Down
1
Tectonic landmass section
2
Biological catalyst
3
Unit of force
5
Ball of burning gas in space
9
Center of an atom or cell
11
Force that attracts objects together
13
Substance with pH below 7