Verified answer

4 Na + O₂ → 2 Na₂O

2 S +  3 O₂ → 2 SO₃

2 Fe + 3 Cl₂ → 2 FeCl₃

2 NO  + O₂  → 2 NO₂

N2  + 3 H₂  → 2 NH₃

2 Al + 6 HCl → 2 AlCl₃  + 3 H₂