PTHH: \(Fe_2O_3+3H_2\underrightarrow{t^o}2Fe+3H_2O\)
\(n_{Fe_2O_3}=\dfrac{3,2}{160}=0,02\left(mol\right)\)
\(n_{Fe\left(lt\right)}=2.n_{Fe_2O_3}=2.0,02=0,04\left(mol\right)\)
\(m_{Fe\left(lt\right)}=0,04.56=2,24\left(g\right)\)
\(H=\dfrac{m_{tt}}{m_{lt}}.100\%=\dfrac{1,792}{2,24}.100\%=80\%\)