$m_{HCl}=20\%.54,75=10,95g$
$⇒n_{HCl}=\dfrac{10,95}{36,5}=0,3mol$
$PTHH :$
$2Al+6HCl\to 2AlCl_3+3H_2$
$Theo$ $pt :$
$n_{Al}=\dfrac{1}{3}.n_{HCl}=\dfrac{1}{3}.0,3=0,1mol$
$⇒m_{Al}=0,1.27=2,7g$
$n_{H_2}=n_{HCl}=0,3mol$
$⇒V_{H_2}=0,3.22,4=6,72l$