Xét P2:
$n_{H_2}=\dfrac{2,24}{22,4}=0,1(mol)$
$Fe+2HCl\to FeCl_2+H_2$
$Fe_2O_3+6HCl\to 2FeCl_3+3H_2$
$\to n_{Fe}=n_{H_2}=0,1(mol)$
Xét P1:
$ n_{Fe_{\text{spu}}}=\dfrac{11,2}{56}=0,2(mol)$
$\to n_{Fe\text{sinh ra}}=0,2-0,1=0,1(mol)$
$Fe_2O_3+3CO\buildrel{{t^o}}\over\to 2Fe+3CO_2$
$\to n_{Fe_2O_3}=0,05(mol)$
$\%m_{Fe}=\dfrac{0,1.56.100}{0.1.56+0,05.160}=41,18\%$
$\%m_{Fe_2O_3}=58,82\%$