Organic Acids (Organic Chemistry)

Total Questions: 29

21. Which acid is used in photography? [U.P.U.D.A./L.D.A. (Pre) 2003]

Correct Answer: (b) Oxalic acid
Solution:Oxalic acid is used in photography. Formic acid is found in ants. Citric acid is found in lemon, and acetic acid is found in vinegar.

22. Which one of the following acids is used in the manufacturing of baking powder? [U.P.P.C.S. (Mains) 2012]

Correct Answer: (c) Tartaric acid
Solution:Tartaric acid is used in the manufacturing of baking powder. This tartaric acid occurs naturally in many plants, particularly in grapes, bananas, and tamarinds. It is commonly combined with baking soda to function as a leavening agent in recipes and is one of the main acids found in wine.

23. The odour of acetic acid resembles that of – [68th B.P.S.C. (Pre) 2022]

Correct Answer: (a) Vinegar
Solution:The odour of acetic acid (CH₃COOH) resembles that of vinegar. Vinegar is a liquid consisting mainly of acetic acid and water. Vinegar is essentially a dilute solution of acetic acid (typically 4-8% acetic acid in water).

24. Vinegar is the solution of which of the following? [U.P.P.C.S. (Pre) 2009 ,42nd B.P.S.C. (Pre) 1997, I.A.S. (Pre) 1993]

Correct Answer: (d) Acetic acid
Solution:Acetic acid (CH₃COOH) or ethanoic acid is an organic acid, which is responsible for the sour taste and pungent smell of vinegar. The physical and chemical properties prove that vinegar is a solution of acetic acid. It is produced from fermentation of ethanol.

25. Which acid is found in Vinegar? [M.P.P.C.S. (Pre) 2010]

Correct Answer: (d) Acetic acid
Solution:Acetic acid is the chief component of vinegar. Vinegar is a liquid consisting mainly of acetic acid (CH₃COOH) and water. The acetic acid is produced by the fermentation of ethanol (formed from sugarcane juice and molasses) by acetic acid bacteria. It is mainly used as a cooking ingredient and as a preservative.

26. Vinegar is chemically known as – [M.P. P.C.S. (Pre) 2016]

Correct Answer: (a) Acetic acid
Solution:Acetic acid is the chief component of vinegar. Vinegar is a liquid consisting mainly of acetic acid (CH₃COOH) and water. The acetic acid is produced by the fermentation of ethanol (formed from sugarcane juice and molasses) by acetic acid bacteria. It is mainly used as a cooking ingredient and as a preservative.

27. The chemical name for vinegar is – [63rd B.P.S.C. (Pre) 2017]

Correct Answer: (c) Acetic acid
Solution:Acetic acid is the chief component of vinegar. Vinegar is a liquid consisting mainly of acetic acid (CH₃COOH) and water. The acetic acid is produced by the fermentation of ethanol (formed from sugarcane juice and molasses) by acetic acid bacteria. It is mainly used as a cooking ingredient and as a preservative.

28. Which of the following statements is correct? [R.A.S./R.T.S. (Pre) 2016]

A. Sugarcane juice is fermented to form vinegar.
B. Vinegar has acetic acid.
C. Benzoic acid is the acid present in Vinegar.
D. Vinegar is used as a preservative.

Code:

Correct Answer: (a) A, B, D
Solution:A. Sugarcane juice is fermented to form vinegar: Sugarcane juice contains sugars, which can be fermented by yeast into ethanol, and then the ethanol can be further fermented by acetic acid bacteria into acetic acid (vinegar).

B. Vinegar has acetic acid: This is a fundamental fact about vinegar.

D.Vinegar is used as a preservative: The acetic acid in vinegar creates an acidic environment that inhibits the growth of many spoilage microorganisms, making it an effective food preservative (e.g., for pickles).

29. Which of the following is not optically active? [Jharkhand P.C.S. (Pre) 2013]

Correct Answer: (a) Glycine
Solution:Glycine is a non-essential, non-optical amino acid. It is also known as a building block for protein. Its formula is NH₂CH₂COOH. An optically active compound should have at least one carbon atom attached to four different groups. Glycine is not optically active because the carbon atom is attached to two hydrogen atoms, one amino group, and one carboxylic group.