\(n_{H_2}=\dfrac{8,96}{22,4}=0,4\left(mol\right)\)
PTHH: \(Zn+H_2SO_4\rightarrow ZnSO_4+H_2\)
0,4<---------------------------0,4
`=>` \(\left\{{}\begin{matrix}\%m_{Zn}=\dfrac{0,4.65}{32,4}.100\%=80,25\%\\\%m_{Cu}=100\%-80,25\%=19,75\%\end{matrix}\right.\)