Question

Arun tested rainwater and found a pH of 5-6 due to presence of hydrogen ions formed by reaction of rainwater with carbon dioxide. When pH of the rainwater drops below 5.6, then it is called acid rain. It affects agriculture and growth of plants because the pH range of soil changed.

(i) Why is acid rain harmful to agriculture, trees and plants?

(ii) What are the chemicals that can be used to mantain the pH of soil in this case?
[2 Marks]

Answer 1

(i) Plants, crops, and trees require an optimum pH for their survival. Due to acid rain, the pH balance of the soil is disturbed and the soil becomes more acidic. The acidic nature of the soil is for the healthy growth of plants, crops, and trees.
[1 Mark]
(ii) Due to acid rain, soil becomes acidic in nature. Acidic soil can be treated with basic substances such as quick lime, lime stone, or chalk to mantain the pH.
[1 Mark]