NEETChemistryAldehydes and Ketones
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): An unknown compound ( C ₈ H ₈ O ) that forms a 2,4-DNP derivative but fails to reduce Fehling's solution must definitively be a ketone. Reason (R): Aromatic aldehydes do not reduce Fehling's solution. In the light of the above statements, choose the most appropriate answer from the options given be
Options
- ABoth Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A)
- BBoth Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A)
- CAssertion (A) is true but Reason (R) is false
- DAssertion (A) is false but Reason (R) is true
Correct answer
D. Assertion (A) is false but Reason (R) is true
Step-by-step solution
Assertion (A) states that a compound with formula C ₈ H ₈ O giving a positive 2,4-DNP test but a negative Fehling's test must definitively be a ketone. While ketones do give a positive 2,4-DNP test and a negative Fehling's test, aromatic aldehydes also exhibit the exact same behavior. For the formula C ₈ H ₈ O , the compound could be a ketone like acetophenone ( C ₆ H ₅ COCH ₃ ) or an aromatic aldehyde like o-, m-, or p-tolualdehyde ( CH ₃ C ₆ H ₄ CHO ). Therefore, it cannot be definitively concluded that the compo