Cho $\begin{cases} Cu: x(mol)\\ Fe: y(mol)\\\end{cases}$
`=> 64x+56y=8,8(g)(1)`
`n_{SO_2}=\frac{4,48}{22,4}=0,2(mol)`
BTe:
$\mathop{Cu}\limits^{0}\to \mathop{Cu}\limits^{+2}+2e$
$\mathop{Fe}\limits^{0}\to \mathop{Fe}\limits^{+3}+3e$
$\mathop{S}\limits^{+6}+2e\to \mathop{S}\limits^{+4}$
`=> 2x+3y=0,4(mol)(2)`
`(1),(2)=> x=0,05(mol), y=0,1(mol)`
`=> m_{Cu}=0,05.64=3,2g`