Cho 28 gam hỗn hợp X gồm Fe; Fe3O4...

D

- Hướng dẫn giải

\(X\left\{ \begin{array}{l}
Fe:x\\
F{e_3}{O_4}:y\\
CuO:z
\end{array} \right. \to Y\left\{ \begin{array}{l}
FeC{l_2}:x + 3y\\
CuC{l_2}:z - 0,05
\end{array} \right. \to \left\{ \begin{array}{l}
Ag:x + 3y\\
AgCl:2x + 6y + 2z - 0,1
\end{array} \right.\)

\( \to \left\{ \begin{array}{l}
56x + 232y + 80z = 28\\
108\left( {x + 3y} \right) + 143,5\left( {2x + 6y + 2z - 0,1} \right) = 132,85\\
2x + 6y + 2z - 0,1 = 8y + 2z + 0,05.2
\end{array} \right. \to \left\{ \begin{array}{l}
x = 0,15\\
y = 0,05\\
z = 0,1
\end{array} \right. \to {m_{F{e_3}{O_4}}} = 1,16.\)