\(Mg+2HCl\rightarrow MgCl2+H2\)
\(n_{H2}=\frac{2,24}{22,4}=0,1\left(mol\right)\)
\(n_{Mg}=n_{H2}=0,1\left(mol\right)\)
\(2Mg+O2-->2MgO\)
\(2Cu+O2-->2CuO\)
\(n_{O2}=\frac{2,24}{22,4}=0,1\left(mol\right)\)
\(n_{KL}=2n_{O2}=0,2\left(mol\right)\)
Mà \(n_{Mg}=0,1\left(mol\right)\Rightarrow n_{Cu}=0,2-0,1=0,1\left(mol\right)\)
\(m=mCu+m_{Mg}=0,1.64+0,1.24=8,8\left(g\right)\)