Question

When basic cations like sodium, calcium and magnesium are leached out in humid places by the action of water.

• A. Stiff soils are formed
• B. Acidic soils are formed
• C. Alkaline soils are formed
• D. The soil level declines

Answer 1

The correct option is B Acidic soils are formed

Soil acidification caused by industrial and mining activities due to acid produced during the reactions. Soil typically carries negative charge on particle surface, and these surfaces attract and hold positively charged base cations such as $Ca,Mg,K,Na,$ and others. With only minor exceptions, soil particles hold hydrogen ions more strongly than these other ions. This means that whenever acidification reactions causes $H^{+}$ ions concentration in the soil to increase, some of the hydrogen ions will then displace these base ions, which becomes susceptible to leaching out of the soil.