Why can bleaching powder lose its effectiveness when kept open in air?
Answer and explanation
Correct answer: It can be affected by moisture and carbon dioxide
Bleaching powder is a reactive salt whose available chlorine can decrease during prolonged exposure to air. Moisture and carbon dioxide promote decomposition or conversion of active constituents into less effective substances. Consequently, an open sample gradually loses bleaching and disinfecting power. Option A is correct. The alternatives involving gold, pure water or iron have no chemical basis and do not explain loss of activity.
Frequently asked questions
What is the correct answer to this question?
It can be affected by moisture and carbon dioxide
Why is this the correct answer?
Bleaching powder is a reactive salt whose available chlorine can decrease during prolonged exposure to air. Moisture and carbon dioxide promote decomposition or conversion of active constituents into less effective substances. Consequently, an open sample gradually loses bleaching and disinfecting power. Option A is correct. The alternatives involving gold, pure water or iron have no chemical basis and do not explain loss of activity.
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.
