$a,PTPƯ:Zn+2HCl\xrightarrow{} ZnCL_2+H_2↑$
$b,n_{Zn}=\dfrac{26}{65}=0,4mol.$
$Theo$ $pt:$ $n_{HCl}=2n_{Zn}=0,8mol.$
$⇒V_{HCl}=\dfrac{0,8}{2}=0,4l.$
$Theo$ $pt:$ $n_{H_2}=n_{Zn}=0,4mol.$
$c,PTPƯ:CuO+H_2\xrightarrow{t^o} Cu+H_2O$
$Theo$ $pt:$ $n_{CuO}=n_{H_2}=0,4mol.$
$⇒m_{CuO}=0,4.80=32g.$
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