If acidified Potassium Dichromate(VI) (K\(_2\)Cr\(_2\)O\(_7\)) acts as oxidizing agent, color changes from

Chemistry

JAMB 2019

A. yellow to green
B. orange to green
C. yellow to red
D. orange to red

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Correct Answer: Option B

Explanation

Potassium dichromate is an oxidising agent in organic chemistry. It is used to oxidize alcohols.

In an aqueous solution the color change exhibited can be used to test for distinguishing aldehydes from ketones. Aldehydes reduce dichromate from the +6 to the +3 oxidation state, changing color from orange to green. This color change arises because the aldehyde can be oxidized to the corresponding carboxylic acid.

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