Practicing Success

Target Exam

CUET

Subject

Chemistry

Chapter

Organic: Biomolecules

Question:

Observation of 'Rhumann's purple' is a confirmatory test for the presence of :

 

Options:

Reducing sugar

Cupric ion

Protein

Starch

Correct Answer:

Protein

Explanation:

Ninhydrin (2,2-dihydroxyindane-1,3-dione) is a chemical used to detect ammonia or primary and secondary amines. When reacting with these free amines (proteins), a deep blue or purple colour known as Ruhemann’s purple is produced.