Assertion: Change in color of acidic solution | vedclass

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(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.

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(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 $C$.

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.

Similar Questions

The oxidation state of chromium in the final product formed by the reaction between $KI$ and acidified potassium dichromate solution is

$Cr _2 O _7^{2-} \rightarrow Cr ^{3+}_{aq}$
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Which of the following reagents causes the aqueous colored solution of acidic $KMnO_4$ to become colorless?

In the reduction of dichromate by $Fe(II)$,the number of electrons involved per chromium atom is:

Which of the following is a redox reaction?

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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.