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AIIMS2015Chemistryd and f Block Elements

Assertion: Change in colour of acidic solution of potassium dichromate by breath is used to test drunken drivers. Reason : Change in colour is due to complexation of alcohol with potassium dichromate.

Options

  1. AIf both assertion and reason are true and reason is the correct explanation of assertion.
  2. BIfboth assertion and reason are true but reason is not the correct explanation of assertion.
  3. CIf assertion is true but reason is false.
  4. DIf both assertion and reason are false.

Correct answer

C. If assertion is true but reason is false.

Step-by-step solution

Acidified K ₂ Cr ₂ O ₇ (orange in colour) solution oxidises alcohol and itself gets reduced to Cr ₂ ( SO ₄ )₃ which is green in colour.

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