$a,PTPƯ:Zn+2HCl\xrightarrow{} ZnCl_2+H_2↑$
$b,n_{Zn}=\dfrac{6,5}{65}=0,1mol.$
$m_{HCl}=100.14,6\%=14,6g.$
$⇒n_{HCl}=\dfrac{14,6}{36,5}=0,4mol$
$\text{Lập tỉ lệ:}$ $\dfrac{0,1}{1}<\dfrac{0,4}{2}$
$⇒HCl$ $dư.$
$⇒n_{HCl}(dư)=0,4-\dfrac{0,1.2}{1}=0,2mol.$
$⇒m_{HCl}(dư)=0,2.36,5=7,3g.$
$c,Theo$ $pt:$ $n_{H_2}=n_{Zn}=0,1mol.$
$⇒V_{H_2}=0,1.22,4=2,24l.$
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