Describe7 marksChallenge
Chlorine undergoes different reactions with cold and hot aqueous sodium hydroxide and is also used in water purification.
(a) Describe, with equations, the reactions of chlorine with cold and with hot aqueous sodium hydroxide. For each reaction, state the changes in oxidation number of chlorine and explain why these are disproportionation reactions.
(b) When chlorine is added to water, it forms hydrochloric acid and chloric(I) acid (HOCl). By writing appropriate equations, explain how HOCl and its conjugate base ClO– are produced and how they act as disinfectants.