UPSC Prelims 2024 Question on – Rainfall and Chemical Weathering of Rocks
Q. Consider the following statements:
Statement I: Rainfall is one of the reasons for the weathering of rocks. Statement II: Rainwater contains carbon dioxide in solution. Statement III: Rainwater contains atmospheric oxygen.
Which one of the following is correct in respect of the above statements?
✅ Correct Answer: (a)
Explanation:
Statement I – Correct: Weathering is the breakdown of rocks due to the action of weather and climate, including rainfall.
Statement II – Correct: Rainwater dissolves atmospheric carbon dioxide to form weak carbonic acid, which promotes chemical weathering.
Statement III – Correct: Rainwater contains dissolved atmospheric oxygen, aiding oxidation reactions during chemical weathering.
Conclusion: Rainfall supplies water, carbon dioxide, and oxygen, all of which accelerate the chemical weathering of rocks.
