a)\(Zn+H2SO4-->ZnSO4+H2\)
\(n_{Zn}=\frac{13}{65}=0,2\left(mol\right)\)
\(n_{H2}=n_{Zn}=0,2\left(mol\right)\)
\(V_{H2}=0,2.22,4=4,48\left(l\right)\)
b)\(Fe+2HCl-->FeCl2+H2\)
\(n_{H2}=\frac{1}{2}n_{HCl}=0,05\left(mol\right)\)
\(V_{H2}=0,05.22,4=1,12\left(l\right)\)