$a,PTPƯ:Zn+2HCl\xrightarrow{} ZnCl_2+H_2↑$
$b,n_{Zn}=\dfrac{13}{65}=0,2mol.$
$Theo$ $pt:$ $n_{H_2}=n_{Zn}=0,2mol.$
$⇒V_{H_2}=0,2.22,4=4,48l.$
$c,Theo$ $pt:$ $n_{HCl}=2n_{Zn}=0,4mol.$
$⇒m_{HCl}=0,4.36,5=14,6g.$
$⇒C\%_{HCl}=\dfrac{14,6}{21,9}.100\%=66,67\%$
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