a, \(n_{H_2}=\dfrac{0,896}{22,4}=0,04\left(mol\right)\)
PTHH: Fe + 2HCl ---> FeCl2 + H2
0,04<-----------------------0,04
\(m_{Cu}=3,52-0,04.56=1,28\left(g\right)\)
Bảo toàn O: \(\left\{{}\begin{matrix}n_{O\left(oxit\right)}=\dfrac{4,8-3,52}{16}=0,08\left(mol\right)\\n_{O\left(CuO\right)}=n_{Cu}=\dfrac{1,28}{64}=0,02\left(mol\right)\end{matrix}\right.\)
=> \(n_{O\left(Fe_xO_y\right)}=0,08-0,02=0,06\left(mol\right)\)
PTHH:CuO + H2 --to--> Cu + H2O
0,02<--------------0,02
=> \(\left\{{}\begin{matrix}\%m_{CuO}=\dfrac{0,02.80}{4,8}.100\%=33,33\%\\\%m_{Fe_xO_y}=100\%-33,33\%=66,67\%\end{matrix}\right.\)
b, CTHH là FexOy
=> x : y = 0,04 : 0,06 = 2 : 3
=> CTHH là Fe2O3