1/
$PTPƯ:Mg+2HCl\xrightarrow{} MgCl_2+H_2↑$
$n_{Mg}=\dfrac{4,8}{24}=0,2mol.$
$Theo$ $pt:$ $n_{MgCl_2}=n_{Mg}=0,2mol.$
$⇒m=m_{MgCl_2}=0,2.95=19g.$
$Theo$ $pt:$ $n_{H_2}=n_{Mg}=0,2mol.$
$⇒V=V_{H_2}=0,2.22,4=4,48l.$
2/
$PTPƯ:Zn+H_2SO_4\xrightarrow{} ZnSO_4+H_2↑$
$n_{Zn}=\dfrac{13}{65}=0,2mol.$
$Theo$ $pt:$ $n_{ZnSO_4}=n_{Zn}=0,2mol.$
$⇒m=m_{ZnSO_4}=0,2.161=32,2g.$
$Theo$ $pt:$ $n_{H_2}=n_{Zn}=0,2mol.$
$⇒V=V_{H_2}=0,2.22,4=4,48l.$
3/
$PTPƯ:2Al+6HCl\xrightarrow{} 2AlCl_3+3H_2↑$
$n_{Al}=\dfrac{8,1}{27}=0,3mol.$
$Theo$ $pt:$ $n_{AlCl_3}=n_{Al}=0,3mol.$
$⇒m=m_{AlCl_3}=0,3.133,5=40,05g.$
$Theo$ $pt:$ $n_{H_2}=\dfrac{3}{2}n_{Al}=0,45mol.$
$⇒V=V_{H_2}=0,45.22,4=10,08l.$
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