Given below are two statements, one labelled as Assertion (A) and other labelled as Reason (R). Select your answer from the codes given below :
Assertion (A): Deep chemical decay of rocks is one of the outstanding features of humid tropical regions
Reason (R) : Intensity of chemical weathering depends to a large extent on abundance of water and higher air temperature
Codes:
Humid Tropics Chemical Decay: Weathering Factors Explained
This question examines the relationship between climate conditions in humid tropical regions and the process of chemical weathering.
Assertion (A) Analysis
The assertion states that deep chemical decay of rocks is a significant characteristic of humid tropical regions.
- This statement is true. Humid tropical climates typically experience high temperatures and abundant rainfall throughout the year.
- These conditions provide the necessary environment for intense chemical reactions that break down rock minerals.
Reason (R) Analysis
The reason states that the intensity of chemical weathering is heavily influenced by the availability of water and higher air temperatures.
- This statement is also true.
- Water is essential for most chemical weathering processes like hydrolysis, oxidation, and dissolution.
- Higher temperatures accelerate the rate of these chemical reactions, leading to faster weathering. For example, reaction rates often approximately double for every 10°C increase in temperature.
Relationship Between (A) and (R)
The reason (R) provides a direct explanation for the assertion (A).
- The specific climatic conditions mentioned in (R) – abundant water and higher temperatures – are precisely the defining characteristics of the humid tropical regions mentioned in (A).
- Therefore, the high intensity of chemical weathering (deep decay) observed in humid tropics is a direct consequence of the factors described in the reason.
Conclusion
Both Assertion (A) and Reason (R) are true statements, and Reason (R) correctly explains why Assertion (A) is true. The abundance of water and high temperatures in humid tropical regions drive the deep chemical decay of rocks.
Selected Option: 1. Both (A) and (R) are true and (R) is the correct explanation of (A).
Important Questions from Geomorphology
Which one of the following is not an igneous rock?
Which of the following statements is/are correct?
1. Hypocenter is the point on the surface of the Earth, nearest to the focus.
2. Velocity of earthquake waves is higher in denser materials.
3. P waves move faster and are the first to arrive at the surface of the Earth.
Select the correct answer using the code given below:
Which one of the following is the lowermost/innermost intrusive igneous rock?
The formation of ‘tors’ on small rocky hills is associated with which among the following?
Which one of the following statements about metamorphic rocks is not correct?
