Answer:
4) 2Na + Cl2 → 2NaCl
5) 2Mg + O2 → MgO
6) 2H2 + 2O2 → 2H2O
Explanation:
4) In order for it to be well balanced, yeah you've got to add 2 in front of Na before the reaction and after the reaction.
5) Add 2 in front of Mg bcuz of the same reason in number 4 but you don't have to add 2 in front of the others bcuz it's alrd well balanced.
6) Tbh for this one, it got me staring at my cat until he freaks out but like yeahh, I tried :')
