\(3Fe+2O_2--to->Fe_3O_4\)
1,5_____1_____________0,5
\(Fe_3O_4+4H_2--to->3Fe+4H_2O\)
0,5_____________________1,5
\(n_{Fe}=\frac{112}{56}=2\left(mol\right)\)
\(n_{O_2}=\frac{22,4}{22,4}=1\left(mol\right)\)
=>Fe dư
=> a=0,5.56+0,5.232=?
=>ΣFe=0,5+1,5=2(mol)
=>mFe=2.56=112(g)