Why can the effectiveness of bleaching powder decrease when it is kept exposed to air for a long time?
Answer and explanation
Correct answer: It can slowly lose available chlorine
Bleaching powder is useful because it contains available chlorine, which is released during suitable reactions and produces the bleaching and disinfecting effect. On prolonged exposure to air, moisture and carbon dioxide, some of this available chlorine may be lost and the material gradually becomes less effective. Thus option A gives the relevant storage-related reason. It does not completely become sodium chloride, gypsum, or washing soda, so options B, C and D are unsuitable.
Frequently asked questions
What is the correct answer to this question?
It can slowly lose available chlorine
Why is this the correct answer?
Bleaching powder is useful because it contains available chlorine, which is released during suitable reactions and produces the bleaching and disinfecting effect. On prolonged exposure to air, moisture and carbon dioxide, some of this available chlorine may be lost and the material gradually becomes less effective. Thus option A gives the relevant storage-related reason. It does not completely become sodium chloride, gypsum, or washing soda, so options B, C and D are unsuitable.
Which subject and chapter does this question cover?
This is a Class 10 Science question. Chapter: Chemical Substances – Nature and Behaviour. Topic: Acids, Bases, and Salts.
