\begin{array}{ll}
& 2KClO_3 \xrightarrow{\text{MnO}_2,\,t^\circ} 2KCl + 3O_2 \quad (\text{A} \to \text{B}) \\[8pt]
& O_2 + 2H_2 \xrightarrow{t^\circ} 2H_2O \quad (\text{B} \to \text{C}) \\[8pt]
& 2H_2O \xrightarrow{\text{điện phân}} 2H_2 + O_2 \quad (\text{C} \to \text{D}) \\[8pt]
& 3H_2 + Fe_2O_3 \xrightarrow{t^\circ} 2Fe + 3H_2O \quad (\text{D} \to \text{E}) \\[8pt]
& Fe + H_2SO_4 \rightarrow FeSO_4 + H_2 \uparrow \quad (\text{E} \to \text{F})
\end{array}
\]