PYQSide ExamsMy practice

Organic Chemistry – Some Basic Principles and Techniques · Question 29

JEE Main 2025 (Online) 3rd April Morning ShiftMCQEasy📈 Topic in 6% papers+4−1
1

The least acidic compound, among the following is: [figure]

  1. B
  2. D
  3. A
  4. C

Answer

(2) D

Solution

(B) Benzenesulphonic acid: a very strong acid (pKa -2.8); the anion is strongly resonance stabilised over three O atoms.

(C) Butanoic acid: carboxylic acid (pKa 4.8); the carboxylate ion is resonance stabilised over two O atoms.

(A) 3-Ethoxyphenol: a phenol (pKa 10); the phenoxide ion is stabilised by delocalisation into the ring.

(D) Ethyl propiolate: only the ≡C–H hydrogen is acidic; the negative charge stays on an sp carbon (pKa of a terminal alkyne is above 20, even with the -CO2Et group).

Acidic strength: B > C > A > D D is the least acidic.

Answer: (2)

JEE Main 2025 (Online) 3rd April Morning Shift

Keep practising — Organic Chemistry – Some Basic Principles and Techniques

2

What is the correct IUPAC name of [figure] ?

  1. 3-Bromo-2-hydroxy-5-nitrobenzoic acid
  2. 2-Hydroxy-3-bromo-5-nitrobenzoic acid
  3. 3-Bromo-4-hydroxy-1-nitrobenzoic acid
  4. 5-Nitro-3-bromo-2-hydroxybenzoic acid
JEE Main 2025 (Online) 3rd April Evening Shift
3

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

  1. Statement I is false but Statement II is true
  2. Statement I is true but Statement II is false
  3. Both Statement I and Statement II are false
  4. Both Statement I and Statement II are true
JEE Main 2025 (Online) 3rd April Evening Shift
4

Consider the following compound (X) [figure] The most stable and least stable carbon radicals, respectively, produced by homolytic cleavage of corresponding C-H bond are :

  1. III, II
  2. II, IV
  3. I, IV
  4. II, I
JEE Main 2025 (Online) 2nd April Morning Shift
5

Designate whether each of the following compounds is aromatic or not aromatic. [figure]

  1. a, c, d, e, h aromatic and b, f, g not aromatic
  2. b, e, f, g aromatic and a, c, d, h not aromatic
  3. a, b, c, d aromatic and e, f, g, h not aromatic
  4. e, g aromatic and a, b, c, d, f, h not aromatic
JEE Main 2025 (Online) 2nd April Morning Shift
6

In 3,3-dimethylhex-1-en-4-yne, there are sp3, sp2 and sp hybridised carbon atoms respectively.

  1. 4, 2, 2
  2. 2, 4, 2
  3. 3, 3, 2
  4. 2, 2, 4
JEE Main 2025 (Online) 2nd April Evening Shift
7

Match List - I with List - II. Choose the correct answer from the options given below :

  1. (A)-(II), (B)-(III), (C)-(IV), (D)-(I)
  2. (A)-(II), (B)-(III), (C)-(I), (D)-(IV)
  3. (A)-(III), (B)-(IV), (C)-(I), (D)-(II)
  4. (A)-(III), (B)-(II), (C)-(I), (D)-(IV)
JEE Main 2025 (Online) 29th January Morning Shift
8

Total number of nucleophiles from the following is : NH3, PhSH, (H3C)2S, H2C=CH2, OH, H3O , (CH3)2 CO, [figure]

  1. 4
  2. 6
  3. 5
  4. 7
JEE Main 2025 (Online) 29th January Morning Shift
9

The correct order of stability of following carbocations is : [figure]

  1. A > B > C > D
  2. C > B > A > D
  3. B > C > A > D
  4. C > A > B > D
JEE Main 2025 (Online) 28th January Morning Shift

All Organic Chemistry – Some Basic Principles and Techniques PYQs →

PDFDownload Organic Chemistry – Some Basic Principles and Techniques PYQs as PDF Free, with answer key and a QR code to every solution — print it or study offline⬇
All JEE Main Chemistry chapters
Physical ChemistrySome Basic Concepts of ChemistryStructure of AtomStates of MatterThermodynamicsEquilibriumRedox ReactionsSolutionsElectrochemistryChemical Kinetics
Inorganic ChemistryClassification of Elements and Periodicity in PropertiesChemical Bonding and Molecular Structurep-Block Elements (Group 13 & 14)p-Block Elements (Group 15–18)d- and f-Block ElementsCoordination Compounds
Organic ChemistryOrganic Chemistry – Some Basic Principles and TechniquesIsomerismHydrocarbonsHaloalkanes and HaloarenesAlcohols, Phenols and EthersAldehydes, Ketones and Carboxylic AcidsAminesBiomoleculesPrinciples Related to Practical Chemistry