Zn + 2HCl → ZnCl2 + H2 (1)
Mg + 2HCl → MgCl2 + H2 (2)
\(n_{H_2}=\frac{6,72}{22,4}=0,3\left(mol\right)\)
Theo PT1,2: \(\Sigma n_{HCl}=2\Sigma n_{H_2}=2\times0,3=0,6\left(mol\right)\)
\(\Rightarrow\Sigma m_{HCl}=0,6\times36,5=21,9\left(g\right)\)
\(\Rightarrow m_{ddHCl.14,6\%}=\frac{21,9}{14,6\%}=150\left(g\right)\)