$a,PTPƯ:2Al+3H_2SO_4\xrightarrow{} Al_2(SO_4)_3+3H_2↑$
$b,n_{Al}=\dfrac{0,54}{27}=0,02mol.$
$Theo$ $pt:$ $n_{Al_2(SO_4)_3}=\dfrac{1}{2}n_{Al}=0,01mol.$
$⇒m_{Al_2(SO_4)_3}=0,01.342=3,42g.$
$c,Theo$ $pt:$ $n_{H_2}=\dfrac{3}{2}n_{Al}=0,03mol.$
$⇒V_{H_2}=0,03.22,4=0,672l.$
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