Why bleaching powder is kept in air tight containers?

Bleaching powder is kept in airtight containers because it is hygroscopic in nature, meaning it readily absorbs moisture from the air. Exposure to moisture can cause bleaching powder to deteriorate and lose its effectiveness.

Here's why keeping bleaching powder in airtight containers is important:

1. Stability: Bleaching powder is a compound called calcium hypochlorite (Ca(OCl)2). When exposed to moisture, it undergoes a reaction with water to form calcium hydroxide (Ca(OH)2) and hypochlorous acid (HOCl). This reaction leads to the decomposition of bleaching powder and reduces its available chlorine content, which is responsible for its bleaching and disinfecting properties.

2. Loss of Chlorine: The hypochlorous acid formed during the reaction with moisture is a volatile compound that can easily escape into the atmosphere. This loss of chlorine gas reduces the overall strength and efficacy of bleaching powder.

3. Caking and Clumping: Absorption of moisture can cause bleaching powder to form lumps and clumps, making it difficult to use and handle. Caked bleaching powder may not dissolve properly in water, affecting its performance.

4. Reduced Shelf Life: Exposure to moisture shortens the shelf life of bleaching powder. When stored in airtight containers, bleaching powder remains dry and retains its effectiveness for a longer period.

To maintain the quality and effectiveness of bleaching powder, it is crucial to keep it in airtight containers in a cool, dry place. Tightly sealing the container helps prevent moisture from entering and ensures that the bleaching powder remains in its original condition until use.