SO2 + MgO = SO2 + KOH = CaO + H2SO4 = CaO + CO2 = CaO + H2O =
SO2 + MgO = MgSO3 SO2 + 2KOH = K2SO3 + H2O CaO + H2SO4 = CaSO4 + H2O CaO + CO2 = CaCO3 CaO + H2O =Ca(OH)2