10th class Chemistry, Chapter 24: Carboxylic Acids MCQs

1. Identify the ester functional group:

1. (A) -COOR ✓
2. (B) -COOH
3. (C) -C=O
4. (D) -CH₂-OH

2. During the oxidation of ethanol by acidified KMnO₄, which element is reduced?

1. (A) K
2. (B) O
3. (C) Mn ✓
4. (D) H

3. Fermentation of foodstuff in the presence of acetic acid bacteria needs a sufficient supply of oxygen. What is the role of oxygen in this process?

1. (A) It enhances the reactivity of bacteria
2. (B) It oxidizes ethanol which is formed during the reaction ✓
3. (C) It inhibits the destruction of bacteria
4. (D) It inhibits the oxidation of acetic acid

4. Which organic acid is used as a component of food?

1. (A) Formic acid
2. (B) Oxalic acid
3. (C) Propanoic acid
4. (D) Acetic acid ✓

5. Which of the following acids is present in apples?

1. (A) Citric acid
2. (B) Tartaric acid
3. (C) Acetic acid
4. (D) Malic acid ✓

6. Which substances will react to produce CH₃-CH₂-CH₂-COOC₂H₅?

1. (A) CH₃CH₂CH₂COOH and CH₃OH
2. (B) CH₃CH₂COOH and CH₃CH₂OH
3. (C) CH₃CH₂CH₂COOH and CH₃CH₂OH ✓
4. (D) CH₃CH₂CH₂CH₂COOH and CH₃OH

7. What is the formula of ester formed by the reaction of methanol with propanoic acid?

1. (A) CH₃COOCH₂CH₃
2. (B) CH₃CH₂COCH₃
3. (C) CH₃CH₂COOCH₃ ✓
4. (D) CH₃CH₂OCOCH₃

8. Which polymer is made by reacting a diol and a dicarboxylic acid?

1. (A) Polyethene
2. (B) Polyester ✓
3. (C) Polystyrene
4. (D) Polyamide

9. Which compound is used as a synthetic fiber?

1. (A) Methyl acetate
2. (B) Polyester ✓
3. (C) Resin
4. (D) n-Amyl acetate

10. Carboxylic acids contain the functional group:

1. (A) -CHO
2. (B) -COOH ✓
3. (C) -NH₂
4. (D) -OH

11. Carboxylic acids are generally ____ acids as compared to mineral acids.

1. (A) stronger than all
2. (B) weaker ✓
3. (C) equal
4. (D) stronger

12. Ethanol is oxidized by acidified KMnO₄ first to:

1. (A) methanol
2. (B) ethanal ✓
3. (C) ethane
4. (D) ethene

13. During oxidation of ethanol with hot acidified KMnO₄ the purple colour changes to:

1. (A) colourless ✓
2. (B) green
3. (C) blue
4. (D) red

14. Vinegar is produced from alcoholic foodstuffs by the action of:

1. (A) yeast without oxygen
2. (B) light
3. (C) heat only
4. (D) bacteria with oxygen ✓

15. Vinegar containing ____ ethanoic acid can be prepared in only 24 hours.

1. (A) 5%
2. (B) 15% ✓
3. (C) 50%
4. (D) 95%

16. The overall reaction of vinegar production is CH₃CH₂OH + O₂ gives:

1. (A) CH₃CHO + H₂
2. (B) C₂H₄ + H₂O
3. (C) CH₃COOH + H₂O ✓
4. (D) CH₄ + CO₂

17. Ethanoic acid reacts with magnesium to give:

1. (A) magnesium chloride
2. (B) magnesium oxide
3. (C) magnesium ethanoate and hydrogen ✓
4. (D) magnesium carbonate

18. Ethanoic acid reacts with sodium hydroxide to give:

1. (A) ethanol
2. (B) hydrogen
3. (C) sodium carbonate
4. (D) sodium ethanoate and water ✓

19. The reaction of carboxylic acids with metal hydroxides is a:

1. (A) neutralization reaction ✓
2. (B) redox only
3. (C) combustion reaction
4. (D) cracking

20. The gas evolved when ethanoic acid reacts with sodium carbonate is:

1. (A) carbon dioxide ✓
2. (B) oxygen
3. (C) hydrogen
4. (D) nitrogen