a,
PTHH: CuO + H2SO4 → CuSO4 + H2O
Mol: x x x
PTHH: Fe2O3 + 3H2SO4 → Fe2(SO4)3 + 3H2
Mol: y 3y y
Ta có: \(\left\{{}\begin{matrix}80x+160y=56\\160x+400y=136\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=0,1\\y=0,3\end{matrix}\right.\)
\(m_{CuO}=0,1.80=8\left(g\right);m_{Fe_2O_3}=56-8=48\left(g\right)\)
b, \(\%m_{CuO}=\dfrac{8.100\%}{56}=14,29\%\)
\(\%m_{Fe_2O_3}=\dfrac{48.100\%}{56}=85,71\%\)
c, \(n_{H_2SO_4}=n_{CuO}+3n_{Fe_2O_3}=0,1+3.0,3=1\left(mol\right)\)
\(\Rightarrow C_{M_{ddH_2SO_4}}=\dfrac{1}{0,2}=5M\)