Fe + H2SO4 === FeSO4 + H2↑
56 2
x 0.3g
56/x=2/0.3g
x=8.4g
(1)铁合金中含铁的质量分数是8.4g/8.5g*100%=98.8%
含碳量 1-98.8%=1.2%