Xanthoprotic Test Quiz

What is the primary purpose of the xanthoprotic test?

• To measure the concentration of proteins in a solution

• To detect non-aromatic amino acids

• To differentiate between proteins and carbohydrates

• To identify aromatic amino acids and proteins containing them

What chemical reaction is the xanthoprotic test based on?

• Oxidation of amino acids

• Nitration of aromatic groups

• Hydrolysis of proteins

• Reduction of phenolic groups

Which of the following is NOT required for the xanthoprotic test?

• Sulfuric acid

• Distilled water

• Sodium hydroxide solution

• Concentrated nitric acid

What is the role of distilled water in the xanthoprotic test?

• To neutralize the reaction

• To enhance the color change

• To serve as a negative control

• To act as a positive control

What color change indicates a positive xanthoprotic reaction after adding alkali?

• Blue to green

• Yellow to orange

• Colorless to pink

• Red to purple

What happens to the protein solution when nitric acid is added during the test?

• It turns blue

• It forms a white or cloudy precipitate

• It becomes clear

• It emits a strong odor

Which of the following proteins is used in the xanthoprotic test to demonstrate a positive reaction?

• Egg albumin

• Collagen

• Keratin

• Hemoglobin

Which amino acid shows a delayed positive reaction in the xanthoprotic test?

• Glutamine

• Phenylalanine

• Tryptophan

• Tyrosine

Why is phenylalanine's reaction in the xanthoprotic test considered weak?

• It reacts too quickly

• It does not dissolve in nitric acid

• It lacks an aromatic group

• Its phenyl group is very stable

What is the significance of the color change from yellow to orange in the xanthoprotic test?

• It shows the test is invalid

• It indicates the presence of non-aromatic amino acids

• It confirms the presence of aromatic amino acids

• It suggests contamination