I am not sure if the equivalents of $\ce{H2}$ in the equation
$$\ce{Mg (s) + 2HCl (aq) -> MgCl2 (aq) + H2}$$
is that of dry or wet hydrogen.
If the $\ce{H2}$ refers to wet hydrogen in the equation, how should I find the volume of dry hydrogen given the pressure of wet and dry hydrogen and the volume of wet hydrogen?