Question

A certain compound gives negative test with ninhydrin and positive test with Benedict's solution. The compound is

• A. A protein
• B. A monosaccharide
• C. A lipid
• D. An amino acid

Answer 1

Answer: (B)

A monosaccharide

Answer 2

Protein gives blue-violet colour with ninhydrin

(2, 2-dihydroxyindane-1, 3-diene)

Carbohydrates gives brown red ppt. with benedict’s solution (Alk. $\mathrm { CuSO } _ { 4 } +$ Citrate ions)