JEE Main · 2021 · 26 Feb 2021 · Shift 2 · Biomolecules

Seliwanoff test and Xanthoproteic test are used for the identification of.......and.....respectively.

(A)ketoses, proteins✓ Correct
(B)aldoses, ketoses
(C)proteins, ketoses
(D)ketoses, aldoses

Answer: (A)

Solution

Seliwanoff test is used to distinguish ketoses from aldoses; it gives a rapid red color with ketoses (like fructose) due to faster dehydration. Xanthoproteic test is used to identify proteins containing aromatic amino acids (like tyrosine, tryptophan); it produces a yellow color with concentrated nitric acid. The correct answer is (A) ketoses, proteins.

JEE Main · 2021 · 26 Feb 2021 · Shift 2 · Single correct option

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