Question

What happen when bleaching powder is kept open in air and chlorine gas is passed through dry slaked lime?

Answer 1

When bleaching powder is kept open in air then it reacts with carbon dioxide and produces calcium carbonate and chlorine gas.

*CaOCl2  +  CO2 ----------->  CaCO3  +  Cl2*

When chlorine gas is passed through dry slaked lime then bleaching powder and water are formed.

*Ca(OH)2  +  Cl2 -------------> CaOCl2  +  H2O*

Hope this will help you.