Across
1
Path of a planet around the sun
3
Form of thermal energy
4
Center of an atom or cell
5
Absolute temperature scale unit
6
Natural satellite of Earth
9
Force that attracts objects together
10
Substance with pH below 7
Down
1
Compound containing oxygen
2
Tectonic landmass section
3
Second lightest element
6
Measure of matter in an object
7
Unit of force
8
Group of similar cells
11
Precious yellow metallic element