配平下列化学方程式.(1)______Fe+______O2 点燃 . ______Fe3O4(2)______CH4+______O2 点燃 . ______CO2+______H2O(3)______Zn+______HCl═______ZnCl2+______H2↑ (4)______Mg+______O2 点燃 . ______MgO (5)______KClO3MnO2.△______ KCl+______ O2↑(6)______CaCO3+______HCl═______CaCl2+______H2O+______CO2↑.