- SO2,MgSO4,CuO{S}{O}_{2}, {M}{g}{S}{O}_{4}, {C}{u}{O}
- CO,SO2,CaO{C}{O}, {S}{O}_{2}, {C}{a}{O}
- CuO, HCl, KOH
- FeO,CuS,MnO2{F}{e}{O}, {C}{u}{S}, {M}{n}{O}_{2}