Qualitative Analysis of Proteins Quiz

What is the purpose of adding sodium hydroxide and copper sulfate in the Biuret test?

• To form a white precipitate

• To form a blue compound

• To form a violet complex

• To form a yellow compound

In the Biuret test, what color indicates the presence of proteins?

• Yellow

• Violet

• Red

• Blue

Which test involves the formation of a violet complex?

• Biuret test

• Xanthoproteic test

• Ninhydrin test

• Millon's test

What reagent is used in the Xanthoproteic test?

• Sodium hydroxide

• Copper sulfate

• Ninhydrin solution

• Concentrated nitric acid

What color change indicates a positive result in the Xanthoproteic test?

• Violet to pink

• Colorless to yellow

• White to red

• Blue to green

Which test uses ninhydrin solution to detect proteins?

• Biuret test

• Xanthoproteic test

• Ninhydrin test

• Millon's test

What color is formed when proteins react with ninhydrin?

• Yellow

• Intense blue

• Brick red

• Violet

What reagent is used in Millon's test?

• Millon's reagent

• Copper sulfate

• Ninhydrin solution

• Concentrated nitric acid

What is the initial color change observed in Millon's test?

• White precipitate

• Yellow solution

• Green precipitate

• Blue complex

What final color indicates a positive result in Millon's test after boiling?

• Yellow

• Brick red

• Violet

• Blue