(C) The Assertion is correct because the breathalyzer test uses the oxidation of ethanol by acidic potassium dichromate $(K_2Cr_2O_7)$,which changes c

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If the Assertion is correct but Reason is incorrect.

(C) The Assertion is correct because the breathalyzer test uses the oxidation of ethanol by acidic potassium dichromate $(K_2Cr_2O_7)$,which changes color from orange to green as $Cr^{6+}$ is reduced to $Cr^{3+}$.The Reason is incorrect because the color change is due to a redox reaction (oxidation of alcohol),not complexation.The chemical reaction is:$2K_2Cr_2O_7 + 8H_2SO_4 + 3C_2H_5OH \longrightarrow 2K_2SO_4 + 2Cr_2(SO_4)_3 + 3CH_3COOH + 11H_2O$Therefore,the correct option is $C$.

Class 11 Chemistry Redox Reactions Redox reaction and Method for balancing Redox reaction

Difficult

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

AIIMS 2006 All AIIMS

A
If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
B
If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
C
If the Assertion is correct but Reason is incorrect.
D
If both the Assertion and Reason are incorrect.