The mole

A gas syringe is used to collect hydrogen produced when excess zinc reacts with 50.0 cm³ of 0.500 mol/dm³ hydrochloric acid.
The equation is
$\text{Zn} + 2\text{HCl} \rightarrow \text{ZnCl}_2 + \text{H}_2$.

What is the maximum volume of hydrogen collected at room temperature and pressure? (Molar gas volume = 24 dm³/mol.)