Question

Name the gas produced when chlorine water is exposed to sunlight

Answer 1

When H2O reacts with Cl2 , it will form HCl and HClO  in presence of sunlight. HClO is unstable and decomposes into HCl and O2gas. The reactions will be :
H2O  + HCl →Sunlight HCl + HClO
2HClO → 2HCl + O2

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