Question

Answer 1

\(Fe+2HCl\rightarrow FeCl_2+H_2\\ FeS+2HCl\rightarrow FeCl_2+H_2S\\ H_2S+Pb\left(NO_3\right)_2\rightarrow2HNO_3+PbS\)

\(n_{PbS}=\dfrac{23,9}{239}=0,1\left(mol\right)\)

Theo PTHH: \(n_{PbS}=n_{H_2S}=n_{FeS}=0,1\left(mol\right)\)

\(m_{FeS}=0,1.88=8,8\left(g\right)\)

\(V_{H_2\left(đktc\right)}=4,48-22,4.0,1=2,24\left(l\right)\\ n_{H_2}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\)

Theo PTHH \(n_{Fe}=n_{H_2}=0,1\left(mol\right)\)

\(\%m_{Fe}=\dfrac{0,1.56}{0,1.56+8,8}.100\%\approx38,89\%\\ \%m_{FeS}=100\%-38,89\%=61,11\%\)