设:含铁质量为X,则含锌为:(12.1g-X)锌产Ag氢铁产Bg氢Zn,Fe都与它反应,所以Zn+H2SO4=ZnSO4+H2↑65212.1g-XAFe+H2SO4=FeSO4+H2↑562XBA=(12.1g-X)*2/65B=2X/56A+B=0.4g即(12.1g-X)*2/65+2X/56=0.4g解的:X=4.9812.1g-X=7.12
