Em tham khảo nha:
\(\begin{array}{l}
4FeO + {O_2} \xrightarrow{t^0} 2F{e_2}{O_3}\\
4 \times |F{e^{ + 2}} \to F{e^{ + 3}} + 1e\\
1 \times |{O_2} + 4e \to 2{O^{ - 2}}\\
4N{O_2} + 2{H_2}O + {O_2} \to 4HN{O_3}\\
4 \times |{N^{ + 4}} \to {N^{ + 5}} + 1e\\
1 \times |{O_2} + 4e \to 2{O^{ - 2}}
\end{array}\)