The color of solution changes from orange -> green when aldehyde is treated with:
Correct answer: C. K2Cr2O7/H+
- A. Ag - mirror test
- B. HCN
- C. K2Cr2O7/H+
- D. NaHSO3
Explanation
K2Cr2O7/H+ is a powerful oxidizing agent commonly used in organic chemistry. In the presence of an aldehyde, the orange-colored K2Cr2O7 solution gets reduced.During the reaction, the aldehyde gets oxidized to a carboxylic acid, while the Cr(VI) ions in K2Cr2O7 get reduced to Cr(III) ions. This reduction causes the color of the solution to change from orange to green.This color change is a result of the reduction of Cr(VI) to Cr(III) and indicates the conversion of the aldehyde to a carboxylic acid.
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About Aldehydes and Ketones
Aldehydes and ketones contain the polar carbonyl group, but aldehydes are generally more readily oxidised and more reactive than ketones. Coverage includes preparation by oxidation or reduction routes, nucleophilic addition of reagents such as hydrogen cyanide and bisulfite, and tests that distinguish aldehydes from ketones.
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