In his experiment that led to the discovery of oxygen, Priestley heated some red mercuric oxide and caused it to break apart. The chemical reaction is:
HgO (s) → Hg (s) + O2 (g)
Is this chemical reaction balanced? Why or why not?
1 No, because the number of oxygen atoms is different on both sides.
2 No, because the number of both mercury and oxygen atoms is different on both sides.
3 Yes, because the number of both mercury and oxygen atoms is the same on both sides.
4 Yes, because the number of mercury atoms is the same on both sides.
