Gọi x,y,z là số mol của fe3o4,mgo,cuo
\(PTHH:Fe_3O_4+4H_2⇌3Fe+4H_2O\left(1\right)\)
________x______________3x_________mol
\(MgO+H_2\rightarrow Mg+H_2O\left(2\right)\)
y____________y________mol
\(CuO+H_2\rightarrow Cu+H_2O\left(3\right)\)
z___________z _________mol
Từ (1),(2),(3) :
\(\Rightarrow\left\{{}\begin{matrix}232x+40y+80z=66,8\left(+\right)\\168x+40t+64z=52,4\left(++\right)\end{matrix}\right.\)
\(Fe_3O_4+8HCl\rightarrow FeCl_2+2FeCl_2+4H_2O\left(4\right)\)
x_______8x____________ mol
\(MgO+2HCl\rightarrow MgCl_2+H_2O\left(5\right)\)
y _______2y _____________mol
\(CuO+2HCl\rightarrow CuCl_2+H_2O\left(6\right)\)
z___2z________________________ mol
\(n_{HCl}=1,1\left(mol\right)\)
Từ 4,5,6 :
\(\left\{{}\begin{matrix}x+y+z=0,325\\8x+2y+2z=1,1\end{matrix}\right.\)
Ta có tỉ lệ :
\(\frac{8x+2y+2z}{x+y+z}=\frac{1,1}{0,325}\)
\(\Leftrightarrow8x+2y+2z=\frac{44}{13x}+\frac{44}{13y}+\frac{44}{13z}\)
\(\Rightarrow\frac{60}{13x}-\frac{18}{13y}-\frac{18}{13z}=0\left(+++\right)\)
Từ (+),(++),(+++)
\(\Rightarrow\left\{{}\begin{matrix}x=0,15\left(mol\right)\\y=0,2\left(mol\right)\\z=0,3\left(mol\right)\end{matrix}\right.\)