Which of the following is NOT correctly matched?
- AAcid present in vinegar - Acetic acid
- BCompound present in bones - Calcium
- CSouring of milk - Nitric acid
- DAcid present in gastric juice - Hydrochloric acid
Show answer and explanation
Correct answer: (c) Souring of milk - Nitric acid
Explanation
Souring of milk is caused by lactic acid produced by bacteria, not nitric acid, so this pair is wrong.
Vinegar contains acetic acid and gastric juice contains hydrochloric acid (HCl) – both correctly matched.
Bones store about 99% calcium, which gives them hardness – also correctly matched.