PYQSide ExamsMy practice

Aldehydes, Ketones and Carboxylic Acids · Question 31

JEE Main 2025 (Online) 3rd April Morning ShiftMCQEasy📈 Topic in 13% papers+4−1
1

Number of molecules from below which cannot give iodoform reaction is : Ethanol, Isopropyl alcohol, Bromoacetone, 2-Butanol, 2-Butanone, Butanal, 2-Pentanone, 3-Pentanone, Pentanal and 3-Pentanol.

  1. 4
  2. 3
  3. 5
  4. 2

Answer

(1) 4

Solution

Iodoform test is given by compounds having CH3CO- group or CH3CH(OH)- group (oxidised to CH3CO- by NaOI), including ethanol.

Give the test: ethanol (CH3CH2OH), isopropyl alcohol (CH3CH(OH)CH3), bromoacetone (CH3COCH2Br), 2-butanol (CH3CH(OH)CH2CH3), 2-butanone (CH3COCH2CH3), 2-pentanone (CH3COCH2CH2CH3).

Do not give the test: butanal (CH3CH2CH2CHO), 3-pentanone (CH3CH2COCH2CH3), pentanal (CH3(CH2)3CHO), 3-pentanol (CH3CH2CH(OH)CH2CH3) — none has a CH3CO- or CH3CH(OH)- unit.

∴ Number of molecules that cannot give the iodoform reaction = 4

Answer: (1)

JEE Main 2025 (Online) 3rd April Morning Shift

Keep practising — Aldehydes, Ketones and Carboxylic Acids

2

The major product (P) in the following reaction is : Ph- O \|C- O \|C-H [ ]KOH Major ProductP

  1. Ph- O \|C-COO K
  2. Ph- OH |CH-CH2OH
  3. Ph- OH |CH-COO K
  4. Ph- O \|C-CH2OH
JEE Main 2025 (Online) 3rd April Evening Shift
3

Given below are two statements: In the light of the above statements, choose the most appropriate answer from the options given below :

  1. Statement I is correct but Statement II is incorrect
  2. Both Statement I and Statement II are correct
  3. Both Statement I and Statement II are incorrect
  4. Statement I is incorrect but Statement II is correct
JEE Main 2025 (Online) 2nd April Morning Shift
4

Consider the following molecules: [figure] The correct order of rate of hydrolysis is :

  1. p > q > r > s
  2. r > q > p > s
  3. p > r > q > s
  4. q > p > r > s
JEE Main 2025 (Online) 2nd April Morning Shift
5

Consider the following reactions. From these reactions which reaction will give carboxylic acid as a major product? Choose the correct answer from the options given below:

  1. A, B and E only
  2. A and D only
  3. B, C and E only
  4. B and E only
JEE Main 2025 (Online) 2nd April Evening Shift
6

The product (P) formed in the following reaction is : [figure]

  1. [figure]
  2. [figure]
  3. [figure]
  4. [figure]
JEE Main 2025 (Online) 29th January Morning Shift
7

[figure] 0.1 mole of compound 'S' will weigh g. (Given molar mass in g mol-1 C : 12, H : 1, O : 16)

JEE Main 2025 (Online) 29th January Morning Shift
8

Both acetaldehyde and acetone (individually) undergo which of the following reactions? Choose the correct answer from the options given below:

  1. C and E Only
  2. A, B and D Only
  3. A, C and E Only
  4. B, C and D Only
JEE Main 2025 (Online) 28th January Morning Shift
9

The compounds that produce CO2 with aqueous NaHCO3 solution are: Choose the correct answer from the options given below:

  1. A and C Only
  2. A, B and E Only
  3. A and B Only
  4. A, C and D Only
JEE Main 2025 (Online) 28th January Morning Shift
10

The total number of compounds from below when treated with hot KMnO4, giving benzoic acid is: [figure] , [figure] , [figure] , [figure] , [figure] , [figure] , [figure] , [figure]

  1. 4
  2. 3
  3. 5
  4. 6
JEE Main 2025 (Online) 28th January Evening Shift

All Aldehydes, Ketones and Carboxylic Acids PYQs →

PDFDownload Aldehydes, Ketones and Carboxylic Acids PYQs as PDF Free, with answer key and a QR code to every solution — print it or study offline⬇
All JEE Main Chemistry chapters