Balancing Redox Equations: two of the atoms in the compounds undergo changes in their charges, with the charge of one of the atoms increasing and the charge of the other decreasing.
A) Fe2O3(s) + 3CO(g) -> 2Fe(s) + 3CO2(g)
B) 2H2(g) + O2(g) -> 2H2O(l)
C) 2HgO(s) -> 2Hg(l) + O2(g)
D) Zn(s) + CuSO4(aq) -> ZnSO4(aq) + Cu(s)