Mg+2HCl--->MgCl2+H2
x-----------------------------x
Fe+2HCl---->FeCl2+H2
y--------------------------------y
n H2=5,6/22,4=0,25(mol)
Theo bài ta có hpt
\(\left\{{}\begin{matrix}24x+56y=9,2\\x+y=0,25\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=0,15\\y=0,1\end{matrix}\right.\)
%m Mg=0,15.24/9,2.100%=39,13%
%m Fe=100-39,19=60,81%
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