Em tham khảo nha :
\(\begin{array}{l}
a)\\
2Na + C{l_2} \to 2NaCl\\
{N_{Na}}:{N_{C{l_2}}}:{N_{NaCl}} = 2:1:2\\
b)\\
F{e_x}{O_y} + yCO \to xFe + yC{O_2}\\
{N_{F{e_x}{O_y}}}:{N_{CO}}:{N_{Fe}}:{N_{C{O_2}}} = 1:y:x:y\\
c)\\
2Al + 3ZnS{O_4} \to A{l_2}{(S{O_4})_3} + 3Zn\\
{N_{Al}}:{N_{ZnSO4}}:{N_{A{l_2}{{(S{O_4})}_3}}}:{N_{Zn}} = 2:3:1:3
\end{array}\)