Answer:
When chlorine reacts with cold and dilute sodium hydroxide, the following reaction takes place:
2NaOH + Cl
2⟶ NaCl + NaClO + H
2O.
When chlorine reacts with hot and concentrated sodium hydoxide, the following reaction takes place:
NaOH + Cl
2⟶ 5NaCl + NaClO
3+ 3H
2O
(the underlined numbers will be in subscript)