CDS 2026 (I) General Knowledge, question 79

Topic: Geography

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Q79

During chemical weathering, when minerals in feldspar change to kaolinite clays, the process is termed as :

  1. (a) Carbonation
  2. (b) Chelation
  3. (c) HydrationCorrect answer
  4. (d) Oxidation

Solution.

Answer: (c) Hydration

  1. Hydration is the chemical addition of water to minerals.
  2. When feldspar takes up water it breaks down into kaolinite clay, so among the options this change is hydration.
  3. Carbonation is carbonic acid acting on carbonates, oxidation is oxygen acting on iron, and chelation is metal ions being bound by organic compounds.

Trap: Geologists call the feldspar to kaolinite change hydrolysis, which is not an option; school geography books list it under hydration.