lâph PTHH theo các sơ đồ sau :
Cu+HNO3-->Cu(NO3)2+NO+H2O
Cu+HNO3-->Cu(NO3)2+NO2+H2O
Fe+H2SO4-->Fe2(SO4)3+SO2+H20
Al+H2SO4-->Al2(SO4)3+SO2+H2O
Al+H2SO4-->Al2(SO4)3+S+H2O
Al+HNO3-->Al(NO3)3+NO+H2O
Al+HNO3-->Al(NO3)3+N2+H2O
Al+HNO3-->Al(NO3)3+NH4NO3+H2O