Câu 11a:
Gọi $x$, $y$ là số mol $Al$, $Fe$
$\to 27x+56y=1,1$ $(1)$
$n_{H_2}=\dfrac{0,896}{22,4}=0,04(mol)$
Bảo toàn e: $3n_{Al}+2n_{Fe}=2n_{H_2}$
$\to 3x+2y=0,04.2=0,08$ $(2)$
$(1)(2)\to x=0,02; y=0,01$
$\%m_{Al}=\dfrac{27x.100}{1,1}=49\%$
$\%m_{Fe}=51\%$
Câu 12a:
Gọi $x$, $y$ là số mol $Fe$, $Zn$
$\to 56x+65y=12,1$ $(1)$
$n_{H_2}=\dfrac{4,48}{22,4}=0,2(mol)$
Bảo toàn e: $2_{Fe}+2n_{Zn}=2n_{H_2}$
$\to 2x+2y=0,2.2=0,4$ $(2)$
$(1)(2)\to x=0,1; y=0,1$
$\%m_{Fe}=\dfrac{56x.100}{12,1}=46,28\%$
$\%m_{Zn}=53,72\%$
