We must use a stoichiometric equation:
$Al(s) + 3HCl(aq) rarr AlCl_3(aq) +3/2H_2(g)uarr$
This equation tells us that $26.98*g$ aluminum metal gives us $33.6*L$ of dihydrogen gas. Why? Because $1$ $mol$ of gas occupies $22.4*L$ at $"STP"$ and $1.5*mol$ were generated.
$"Moles of aluminum"$ $=$ $(30.2*g)/(26.98*g*mol^-1)$ $=$ $1.12*mol$.
Given the , $3/2xx1.12*cancel(mol)xx22.4*L*cancel(mol^-1)$ are generated.