PYQSide ExamsMy practice

Organic Chemistry – Some Basic Principles and Techniques · Question 3

JEE Main 2026 (Online) 6th April Evening ShiftMCQMedium📈 Topic in 16% papers+4−1
1

Shown below is the structure of methyl acetate with three different α, β and γ carbon - oxygen bonds. [figure] The correct order of bond lengths of these bonds is :

  1. α > β > γ
  2. α < β < γ
  3. α = β = γ
  4. α < β = γ

Answer

(2) α < β < γ

Solution

Resonance in the ester group: the lone pair on the ether O (β-bond O) is delocalised towards C=O:

CH3- O \|C-O-CH3 CH3- O |C= O-CH3

α (C=O): double bond, slightly lengthened by resonance ⇒ shortest

β (C–O of ester): single bond with partial double-bond character ⇒ intermediate

γ (O–CH3): pure single bond to an sp3 carbon ⇒ longest

∴ α < β < γ

Answer: (2)

JEE Main 2026 (Online) 6th April Evening Shift

Keep practising — Organic Chemistry – Some Basic Principles and Techniques

2

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

  1. Both Statement I and Statement II are correct
  2. Both Statement I and Statement II are incorrect
  3. Statement I is correct but Statement II is incorrect
  4. Statement I is incorrect but Statement II is correct
JEE Main 2026 (Online) 5th April Morning Shift
3

IUPAC name of the some alkenes are given below. Find out the correct stability order. Choose the correct answer from the options given below :

  1. C > A > B > D
  2. C > A > D > B
  3. B > D > A > C
  4. A > B > C > D
JEE Main 2026 (Online) 5th April Evening Shift
4

Identify the correct IUPAC name of hydrocarbon (x) containing three primary carbon atoms and with molar mass 72 g mol-1.

  1. 1, 1 - Dimethylcyclopropane
  2. 2, 2 - Dimethylpropane
  3. 2 - Methylbutane
  4. n-pentane
JEE Main 2026 (Online) 5th April Evening Shift
5

Increasing order of electron withdrawing power of following functional groups is : a. -CN b. -COOH c. -NO2 d. -I

  1. c < b < d < a
  2. c < a < b < d
  3. d < b < a < c
  4. a < b < c < d
JEE Main 2026 (Online) 4th April Morning Shift
6

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

  1. A-III, B-I, C-II, D-IV
  2. A-III, B-IV, C-II, D-I
  3. A-III, B-IV, C-I, D-II
  4. A-I, B-III, C-IV, D-II
JEE Main 2026 (Online) 4th April Evening Shift
7

Consider the following molecules/species : [figure] The correct order of carbon-oxygen double bond length is :

  1. x > y > z
  2. y > z > x
  3. z > x > y
  4. x > z > y
JEE Main 2026 (Online) 4th April Evening Shift
8

The descending order of acidity among the following compounds is : [figure] Choose the correct answer from the options given below :

  1. B > D > E > A > C
  2. D > B > E > A > C
  3. C > A > B > D > E
  4. D > E > B > A > C
JEE Main 2026 (Online) 4th April Evening Shift
9

The strongest conjugate acid will result from:

  1. [figure]
  2. [figure]
  3. [figure]
  4. [figure]
JEE Main 2026 (Online) 4th April Evening Shift
10

In IUPAC nomenclature, the correct order of decreasing priority of functional group is :

  1. -CONH2, >C=O, -CHO, -NH2, -C C-
  2. -CONH2, -COOCH3, -CHO, -NH2, -OH
  3. -CONH2, -CHO, >C=O, -NH2, -C C-
  4. -CONH2, -CHO, -CN, -NH2, -C C-
JEE Main 2026 (Online) 2nd April Morning Shift
11

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

  1. Both Statement I and Statement II are true
  2. Both Statement I and Statement II are false
  3. Statement I is true but Statement II is false
  4. Statement I is false but Statement II is true
JEE Main 2026 (Online) 2nd April Evening 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