Question

When concentrated nitric acid is added to a sample of cooking oil to detect the adulteration, it turns

• A. Yellow in colour
• B. Black in colour
• C. Reddish-brown in colour
• D. Yellowish-brown in colour

Answer 1

The correct option is C

Reddish-brown in colour

The correct answer is C.

Explanation for correct answer:

Test for oil adulteration-

1. To detect the presence of argemone oil in cooking oil or fat, take some quantity of oil in a test tube and an equal quantity of concentrated nitric acid and shake carefully.
2. A red to reddish-brown color in the lower layer would indicate the presence of argemone oil.

Final answer: When concentrated nitric acid is added to a sample of cooking oil to detect the adulteration, it turns reddish-brown.