\(a.n_{Zn}=\dfrac{38}{65}=0.58\left(mol\right)\)
\(b.n_S=\dfrac{96}{32}=3\left(mol\right)\)
\(c.n_{H_2O}=\dfrac{36}{18}=2\left(mol\right)\)
\(d.n_{H_2SO_4}=\dfrac{49}{98}=0.5\left(mol\right)\)
\(e.n_{MgCl_2}=\dfrac{38}{95}=0.4\left(mol\right)\)
\(f.n_{Al}=\dfrac{5.4}{27}=0.2\left(mol\right)\)