常见的金属是Fe,Al,Cr
可使金属钝化的酸是,浓硝酸,浓硫酸
4Al+12HNO3浓=2Al2O3+12NO2↑+6H2O
4Fe+12HNO3浓=2Fe2O3+12NO2↑+6H2O
2Al+3H2SO4浓=Al2O3+3SO2↑+3H2O
2Fe+3H2SO4浓=Fe2O3+3SO2↑+3H2O