Đặt [imath]n_{Fe}=x \ (mol), \ n_{Al}=y \ (mol) \ (x,y>0)[/imath]
[imath]n_{H_2 \ (dktc)}= \dfrac{0,56}{22,4}= 0,025 \ (mol)[/imath]
View attachment 221996
Ta có hệ: [imath]
\left\{\begin{matrix}
56x+27y=0,83 \\
x+ \dfrac{3}{2}y=0,025
\end{matrix}\right. \Leftrightarrow
\left\{\begin{matrix}
x=0,01 \\
y=0,01
\end{matrix}\right.
[/imath]
[imath]m_{Fe}= 0,01.56= 0,56 \ (g), \ m_{Al}= 0,01.27= 0,27 \ (g)[/imath]
[imath] \% m_{Fe}= \dfrac{0,56}{0,83}.100= 67,47 \ ( \%), \ \% m_{Al}= 32,53 \ ( \%)[/imath]