Question

_________ gas is used to disinfect the water in the swimming pool.

Answer 1

Uses of chlorine:

• When the water in a pool is not changed or when it stays for a longer period of time, various bacteria develop in water which makes water harmful and not safe for swimmers.
• Chlorine gas(${\mathrm{Cl}}_2$) then is added to water, to keep it germ-free.
• To sanitize the pool various Chlorine-based compounds including Sodium hypochlorite/liquid bleach($\mathrm{NaOCl}$), Calcium hypochlorite($\mathrm{Ca}{\left(\mathrm{OCl}\right)}_2$), Chlorine gas, etc. are added to it.
• These compounds when coming in contact with water give Hypochlorous acid $\left(\mathrm{HOCl}\right)$, which acts as a sanitizer for the water and kills germs and bacteria like Salmonella and E. coli and prevents swimmers from getting diarrhea and ear infection.

Hence, Chlorine gas is used to disinfect the water in the swimming pool.