Which one of the following is <strong>not</strong> an example of an oxidation reaction?

  1. A. The taste of butter changes if left for a longer period
  2. B. A white substance is formed when an aqueous solution of barium chloride is mixed with sodium sulphate solution
  3. C. A reddish-brown powder gets coated on articles made of iron
  4. D. Wine gets sour with time

Correct Answer: B. A white substance is formed when an aqueous solution of barium chloride is mixed with sodium sulphate solution

Explanation

Mixing barium chloride with sodium sulphate results in the precipitation of barium sulphate. This is a double displacement reaction, not an oxidation-reduction reaction.

Related questions on Chemistry

Practice more CDS General Knowledge questions