Solution:Concept: The chemical formula of bleaching powder is and its structural formula has , and ions.
The compound calcium hypochlorite has bleaching actions. When it is in an aqueous solution, it exerts a bleaching effect or functions as a bleaching agent. Therefore, only one hypochlorite ion is active or breaks down to produce nascent oxygen and chloride ions when it is dissolved in water, while the other hypochlorite ion is stable in the solution.
The reactions are:
is calcium oxychloride and it acts as the bleaching agent.
Remember that chlorine here shows two types of oxidation states. It is -1 in and +1 in .
Hence, the correct answer is option 3.