Question

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R)
Assertion (A): Ketoses give Seliwanoff's test faster than Aldoses
Reason (R): Ketoses undergo -elimination followed by formation of furfural
In the light of the above statements, choose the correct answer from the options given below:

• A. Both (A) and (R) are true but $( R )$ is not the correct explanation of (A)
• B. (A) is false but (R) is true
• C. (A) is true but (R) is false
• D. Both (A) and (R) are true and (R) is the correct explanation of (A)

Hint:

When studying organic tests, remember the key principle behind each test. For example, Seliwanoff’s test differentiates between Ketoses and Aldoses based on the rate of dehydration to form furfural.

Answer 1

The Correct Option is C

Seliwanoff’s test is a differentiating test for Ketose and Aldose. This test relies on the principle that the keto hexose are more rapidly dehydrated to form 5-hydroxy methyl furfural when heated in acidic medium which on condensation with resorcinol gives a red or brown coloured complex, forming rapidly indicating a positive test.