1. Which of the following is an aliphatic aldehyde?
Answer:
Explanation:
Acetaldehyde is an aldehyde with an alkyl group, hence it is aliphatic.
2. The IUPAC name for the compound CH3-CO-CH2-CH3 is:
Answer:
Explanation:
The compound is a ketone with four carbon atoms, and the carbonyl group is at the second position.
3. Which of the following reagents cannot oxidize aldehydes?
Answer:
Explanation:
Lucas reagent is primarily used to distinguish between primary, secondary, and tertiary alcohols.
4. Acetic acid on reduction gives:
Answer:
Explanation:
Reduction of carboxylic acids results in the formation of primary alcohols.
5. Which of the following compounds can give a positive iodoform test?
Answer:
Explanation:
Methyl ketones, like propanone, give a positive iodoform test.
6. Which of the following compounds is aromatic in nature?
Answer:
Explanation:
Benzaldehyde contains a benzene ring, making it aromatic.
7. Which of the following compounds has the highest boiling point?
Answer:
Explanation:
Carboxylic acids can form dimeric structures through hydrogen bonding, leading to higher boiling points.
8. The oxidation of primary alcohols gives:
Answer:
Explanation:
Primary alcohols first oxidize to aldehydes and can further oxidize to carboxylic acids.
9. Which reagent is used for distinguishing between aldehydes and ketones?
Answer:
Explanation:
Tollen's reagent gives a silver mirror test with aldehydes but not with ketones.
10. Acetone reacts with which of the following to form an oxime?
Answer:
Explanation:
Reaction with hydroxylamine (NH2OH) forms an oxime.
11. Which of the following compounds can form a hemiacetal?
Answer:
Explanation:
Both aldehydes and ketones can react with alcohols to form hemiacetals.
12. The Cannizzaro reaction involves:
Answer:
Explanation:
In the Cannizzaro reaction, one molecule of an aldehyde is oxidized to a carboxylic acid, and another is reduced to an alcohol.
13. Which of the following compounds has the highest acid strength?
Answer:
Explanation:
Carboxylic acids are the most acidic among the given options.
14. Which of the following reactions involves the formation of a cyanohydrin?
Answer:
Explanation:
Reaction with KCN leads to the formation of cyanohydrin.
15. A compound that can undergo aldol condensation is:
Answer:
Explanation:
Both benzaldehyde and acetone have alpha-hydrogen atoms, which are required for aldol condensation.
16. The reaction of carboxylic acid with thionyl chloride (SOCl2) gives:
Answer:
Explanation:
Thionyl chloride converts carboxylic acids to their corresponding acid chlorides.
17. Which of the following compounds gives a brisk effervescence with sodium bicarbonate?
Answer:
Explanation:
Carboxylic acids react with sodium bicarbonate to release carbon dioxide gas.
18. The functional group of ketones is:
Answer:
Explanation:
Ketones have a carbonyl functional group.
19. In the presence of a base, acetaldehyde can self-condense to form:
Answer:
Explanation:
This is an aldol reaction, and the product is 3-hydroxybutanal.
20. The compound formed by the oxidation of a secondary alcohol is:
Answer:
Explanation:
Secondary alcohols on oxidation give ketones.