JEE Main · Chemistry · Organic Chemistry: Some Basic Principles and Techniques
Resonance and Hyperconjugation: JEE Main previous year questions
28 questions in the 108 JEE Main shifts Lumi analysed, in 8 of 8 years. Pattern: Asked most years. 12 came in 2024–26. Here is how it is asked and which ideas come back.
- Questions
- 28
- in 26 of 108 shifts
- Years asked
- 8/8
- last asked 2026
- Weighted estimate
- 0.3
- model; history: 0.3 a shift on average, typically 0.1–0.4
Key findings
- 01
Asked in 8 of 8 years with analysed shifts and in 26 of 108 shifts: 28 questions, #119 of 196 topics. It came in every year with analysed shifts.
- 02
37% of its questions since 2020 tested an idea no earlier year had asked; 8 repeated an idea from the year before.
- 03
The most repeated idea is Mesomeric Effect, asked 9 times in 9 shifts (2020, 2024, 2026), most often as “statement i/ii on mesomeric effect”.
- 04
JEE Main has asked 7 of the 42 ideas in this topic; 29 have never been asked, directly or inside another question.
- 05
Mostly asked as single correct (46%); 11% need a numerical answer, 18% are easy and 7% hard.
- 06
The skill tested most is conceptual (75%), then application (11%).
Questions a shift, year by year
Out of the 25 Chemistry questions in a shift. Years differ in how many shifts Lumi analysed, so each year is scaled to one shift.
Raw count: 2017: 1 in 1 shift · 2020: 5 in 12 shifts · 2021: 5 in 24 shifts · 2022: 3 in 24 shifts · 2023: 2 in 12 shifts · 2024: 8 in 18 shifts · 2025: 1 in 8 shifts · 2026: 3 in 9 shifts.
- Up to 2023
- 0.3
- a shift, of 25
- Since 2024
- 0.3
- 0.0
- Usual gap
- 1.3 yrs
- between years asking it
- Shifts with it
- 26/108
- 24% of analysed shifts
How it is asked
Difficulty, format and skill
Across all 28 questions on Resonance and Hyperconjugation since 2017.
Difficulty
QUESTIONS- Easy5 · 18%
- Medium21 · 75%
- Hard2 · 7%
Format
SHARE- Single correct · 13 Q46%
- Diagram based · 9 Q32%
- Numerical value · 3 Q11%
- Two statements · 1 Q4%
- Match the list · 1 Q4%
- Other · 1 Q4%
Skill tested
SHARE- Conceptual · 21 Q75%
- Application · 3 Q11%
- Multi-step · 2 Q7%
- Recall · 1 Q4%
- Diagram reading · 1 Q4%
Repeats
New idea, or one asked before?
Each column is a year. Blue questions tested an idea no earlier year had asked; navy ones went back to an idea from an earlier year. 2017 is the first year, so everything in it counts as new. Heights are question counts, and Lumi analysed 1 to 24 shifts a year, so compare the split inside a column rather than heights across years.
- Idea asked for the first time
- Idea asked in an earlier year
Coverage of the topic
JEE Main has asked 7 of the 42 ideas in this topic. 29 have never been asked yet.
- Asked directly7 · 17%
- Touched inside another question6 · 14%
- Never asked29 · 69%
Ideas come from Lumi’s JEE syllabus map. A never-asked idea is not a safe skip: across all of JEE Main, 22% of questions since 2024 tested an idea no earlier year had asked.
Drill down
Chapter, idea, question
Every idea JEE Main tested in this topic, with its eight years. Open one to read the questions.
5 ideas inside
Squares are the 8 years with analysed shifts, 2017 to 2026. A number is the questions that year when there is more than one; the shade is scaled to one shift, so a year with more analysed shifts (1 to 24 a year) does not look darker. Share is of the level above.
Ideas
Every idea inside this topic
7 different ideas were tested; 5 came more than once.
statement i/ii on mesomeric effect
Single correct · 9 shifts · 1 numericalleast resonance stabilised among ring structures
Diagram based · 7 shiftsdefinition recall
Single correct · 4 shiftsorder/ranking of alkene stability
Numerical value · 3 shifts · 1 numericalidentify incorrect resonance structure
Single correct · 3 shiftscount hyperconjugation structures of carbocation
Numerical value · 1 shift · 1 numericalorder of heat of combustion of alkadienes
Diagram based · 1 shift
| Idea | Years asked | Times | Shifts | Format | Numerical |
|---|---|---|---|---|---|
| Mesomeric Effectstatement i/ii on mesomeric effect | 9 | 9 | Single correctConceptual | 1 | |
| Huckel's Ruleleast resonance stabilised among ring structures | 7 | 7 | Diagram basedConceptual | – | |
| Relative Stabilitydefinition recall | 4 | 4 | Single correctConceptual | – | |
| Hyperconjugationorder/ranking of alkene stability | 3 | 3 | Numerical valueApplication | 1 | |
| Resonance Structuresidentify incorrect resonance structure | 3 | 3 | Single correctConceptual | – | |
| Counting Alpha-Hydrogenscount hyperconjugation structures of carbocation | 1 | 1 | Numerical valueMulti-step | 1 | |
| Heat of Hydrogenationorder of heat of combustion of alkadienes | 1 | 1 | Diagram basedConceptual | – |
Times and shifts count every analysed shift. Across JEE Main, 78% of questions since 2024 went back to an idea an earlier year had asked; the rest were new. All repeated ideas
Every question
Resonance and Hyperconjugation questions, year by year
The opening words of each question as it appeared in the official paper, with the idea it tested. Open one for its options and the official answer.
JEE Main 20263 questions in 3 shifts
- 2 Apr, Shift 2Q63Given below are two statements: Statement I: In…
Idea: Mesomeric Effect
MediumSingle correct - 5 Apr, Shift 2Q63IUPAC name of the some alkenes are given below. Find out the correct stability order. A. 2-Methylbut-2-ene B. -But-2-ene C. 2,…
Idea: Hyperconjugation
Asked the year beforeMediumSingle correct - 6 Apr, Shift 2Q63Shown below is the structure of methyl acetate with three different , and carbon - oxygen bonds. The correct…
Idea: Mesomeric Effect
MediumDiagram based · figure
JEE Main 20251 question in 1 shift
- 3 Apr, Shift 2Q65Given below are two statements: Statement I : Hyperconjugation is not a permanent effect. Statement II : In general, greater the number of…
Idea: Hyperconjugation
Asked the year beforeEasyTwo statements
JEE Main 20248 questions in 6 shifts
- 4 Apr, Shift 1Q74Match List I with List II : List - I (Mechanism steps) List - II (Effect) (A) [structure: aniline, lone pair on NH donated into ring,…
Idea: Mesomeric Effect
MediumMatch the list · figure - 6 Apr, Shift 2Q88Number of carbocations from the following that are not stabilized by hyperconjugation is ________.
Idea: Hyperconjugation
New ideaMediumNumerical value · figure - 9 Apr, Shift 1Q71Relative stability of the contributing structures is : (I) …
Idea: Relative Stability
MediumSingle correct · figure - 9 Apr, Shift 1Q89How many compounds among the following compounds show inductive, mesomeric as well as hyperconjugation effects ? [figure: eight…
Idea: Mesomeric Effect
MediumNumerical value · figure - 9 Apr, Shift 2Q73The correct stability order of the following resonance structures of is I:…
Idea: Relative Stability
MediumSingle correct · figure - 1 Feb, Shift 2Q73The functional group that shows negative resonance effect is :
Idea: Mesomeric Effect
EasySingle correct - 29 Jan, Shift 1Q72The interaction between bond and lone pair of electrons present on an adjacent atom is responsible for
Idea: Mesomeric Effect
EasySingle correct - 29 Jan, Shift 1Q73The difference in energy between the actual structure and the lowest energy resonance structure for the given compound is
Idea: Relative Stability
EasySingle correct
JEE Main 20232 questions in 2 shifts
- 11 Apr, Shift 1Q89[figure: bicyclic (hydrindane-type) skeleton: cyclohexane fused to cyclopentane; Me at the ring-fusion carbon, adjacent cyclopentane…
Idea: Counting Alpha-Hydrogens
New ideaHardNumerical value · figure - 12 Apr, Shift 1Q74Correct statements for the given reaction are : [figure: 'A' -> 'B' with OH (2eq)] A. Compound 'B' is aromatic B. The completion of…
Idea: Huckel's Rule
Asked the year beforeMediumOther · figure
JEE Main 20223 questions in 3 shifts
- 30 Jul, Shift 2Q43Which of the following is unstable?
Idea: Huckel's Rule
Asked the year beforeMediumDiagram based · figure - 27 Jun, Shift 2Q72Which of the following is most stable?
Idea: Huckel's Rule
Asked the year beforeMediumDiagram based · figure - 29 Jun, Shift 2Q73Which of the following carbocations is most stable?
Idea: Relative Stability
New ideaMediumDiagram based · figure
JEE Main 20215 questions in 5 shifts
- 26 Aug, Shift 2Q42Which one of the following compounds is not aromatic ?
Idea: Huckel's Rule
Asked the year beforeMediumDiagram based · figure - 24 Feb, Shift 2Q43Which one of the following compounds is non-aromatic ?
Idea: Huckel's Rule
Asked the year beforeEasySingle correct · figure - 22 Jul, Shift 2Q43Which one of the following compounds does not exhibit resonance ?
Idea: Resonance Structures
New ideaMediumSingle correct · figure - 25 Jul, Shift 1Q41Which one among the following resonating structures is not correct ?
Idea: Resonance Structures
New ideaMediumDiagram based · figure - 25 Jul, Shift 2Q38Identify the species having one -bond and maximum number of canonical forms from the following :
Idea: Resonance Structures
New ideaMediumSingle correct
JEE Main 20205 questions in 5 shifts
- 8 Jan, Shift 1Q41Arrange the following compounds in increasing order of COH bond length : methanol, phenol, p-ethoxyphenol
Idea: Mesomeric Effect
New ideaMediumSingle correct - 8 Jan, Shift 2Q41The major product in the following reaction is : [figure]
Idea: Huckel's Rule
Asked the year beforeMediumDiagram based · figure - 9 Jan, Shift 1Q44The correct order of heat of combustion for following alkadienes is : (a) [drawn structure] (b) [drawn structure] (c) [drawn structure]
Idea: Heat of Hydrogenation
New ideaHardDiagram based · figure - 9 Jan, Shift 2Q40Which of the following has the shortest C-Cl bond ?
Idea: Mesomeric Effect
New ideaMediumSingle correct - 4 Sep, Shift 2Q39Among the following compounds, which one has the shortest CCl bond ?
Idea: Mesomeric Effect
New ideaMediumDiagram based · figure
JEE Main 20171 question in 1 shift
- 2 Apr (offline)Q54Which of the following molecules is least resonance stabilized ?
Idea: Huckel's Rule
MediumSingle correct · figure
Questions from the official JEE Main Paper 1 shifts published by NTA (CBSE for 2017). Questions NTA dropped are left out. Topic and idea tags, counts and notes are Lumi’s.