Integer Answer Type Questions: Aldehydes, Ketones & Carboxylic Acids | JEE Advanced | 35 Years Chapter wise Previous Year Solved Papers for JEE PDF Download

Q.1. In the scheme given below, the total number of intramolecular aldol condensation products formed from ‘Y’ is

Ans. 1

Solution. 

The number of intra molecular aldol condensation products (α, β –unsaturated carbonyl compound formed from Y is 1.

Q.2. Amongst the following, the total number of compounds soluble in aqueous NaOH is

Ans. 4

Solution. All carboxylic acids and phenols are soluble in aqueous NaOH. Four compounds are soluble in aqueous NaOH.

Q.3. The total number of carboxylic acid groups in the product P is       

Ans. 2

Solution. 

No. of –COOH group is '2'

Q.4. Consider all possible isomeric ketones, including stereoisomers of MW = 100. All these isomers are independently reacted with NaBH₄ (NOTE: stereoisomers are also reacted separately). The total number of ketones that give a racemic product(s) is/are 

Ans. 5

Solution. General molecular formula for ketones is C_nH2_nO

∴ C_nH_2nO = 100 or 12n + 2n + 16 = 100, n = 6

Possible isomeric ketones with 6 carbon atoms are

Note that only isomer III has a chiral carbon so on reduction with NaBH₄ it will give diastereomeric alcohols, while all other five isomers will give racemic mixture.

Q.5. Among the following, the number of reaction (s) that produce(s) benzaldehyde is

Ans. 4

Solution.