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).