Which of the following pairs is/are NOT correctly matched?

Question

Which of the following pairs is/are NOT correctly matched?

(Acid) — (Acid found in)

1. Lactic acid — Curd

2. Tartaric acid — Grapes

3. Acetic acid — Potato

Select the correct answer from the code given below:

1. A. 1 and 2
2. B. Only 3 (Correct answer)
3. C. 2 and 3
4. D. Only 1

Correct Answer

Option B — Only 3

Detailed Solution & Explanation

The correct answer is Only 3.

Key Points

• 3. Acetic acid — Potato is NOT correctly matched. Acetic acid (CH₃COOH) is found in vinegar, not potato. Dilute acetic acid of about 5-8% *is* vinegar.
• 1. Lactic acid — Curd ✓. Produced when *Lactobacillus* bacteria ferment the lactose in milk.
• 2. Tartaric acid — Grapes ✓. Also present in tamarind.
• Only pair 3 is wrong, giving option (b).

Additional Information

• Natural acids worth memorising:
  • Citric acid — citrus fruits (lemon, orange)
  • Malic acid — apple
  • Oxalic acid — tomato, spinach
  • Formic (methanoic) acid — ant sting and nettle sting
  • Butyric acid — rancid butter
  • Ascorbic acid — Vitamin C, in amla and citrus fruits
  • Tannic acid — tea
• Glacial acetic acid is pure (anhydrous) acetic acid, so called because it freezes to an ice-like solid just below room temperature at about 16.6°C.
• A baking soda paste relieves an ant sting because the mild base neutralises the formic acid injected.