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AIIMS 2015
Exam
AIIMS
Year
2015
Subject
Chemistry
Chapter
d and f Block Elements

AIIMS 2015 · Chemistry · d and f Block Elements

Assertion: Change in colour of acidic solution of potassium...

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 K2Cr2O7\mathrm{K}_2 \mathrm{Cr}_2 \mathrm{O}_7 (orange in colour) solution oxidises alcohol and itself gets reduced to \mathrm{Cr}_2\left(\mathrm{SO}_4\right)_3 which is green in colour.
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