$a,PTPƯ:Zn+2HCl\xrightarrow{} ZnCl_2+H_2↑$
$n_{Zn}=\dfrac{13}{65}=0,2mol.$
$Theo$ $pt:$ $n_{H_2}=n_{Zn}=0,2mol.$
$⇒V_{H_2}=0,2.22,4=4,48l.$
$b,Theo$ $pt:$ $n_{HCl}=2n_{Zn}=0,4mol.$
$\text{Đổi 200 ml = 0,2 lít.}$
$⇒V_{HCl}=\dfrac{0,4}{0,2}=2M.$
$c,PTPƯ:Fe_3O_4+4H_2\xrightarrow{t^o} 3Fe+4H_2O$
$Theo$ $pt:$ $n_{Fe}=\dfrac{3}{4}n_{H_2}=0,15mol.$
$⇒m_{Fe}=0,15.56=8,4g.$
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