JEE Main · Chemistry · Hydrocarbons
Alkenes and Alkynes: JEE Main previous year questions
82 questions in the 108 JEE Main shifts Lumi analysed, in 8 of 8 years. Pattern: Asked most years. 28 came in 2024–26. Here is how it is asked and which ideas come back.
- Questions
- 82
- in 70 of 108 shifts
- Years asked
- 8/8
- last asked 2026
- Weighted estimate
- 0.7
- model; history: 0.9 a shift on average, typically 0.6–1.0
Key findings
- 01
Asked in 8 of 8 years with analysed shifts and in 70 of 108 shifts: 82 questions, #13 of 196 topics. It came in every year with analysed shifts.
- 02
30% of its questions since 2020 tested an idea no earlier year had asked; 41 repeated an idea from the year before.
- 03
The most repeated idea is Reductive Ozonolysis Products, asked 16 times in 16 shifts (2020, 2021, 2022, 2023, 2024, 2025, 2026), most often as “deduce alkene from ozonolysis products”.
- 04
JEE Main has asked 24 of the 46 ideas in this topic; 14 have never been asked, directly or inside another question.
- 05
Mostly asked as diagram based (39%); 16% need a numerical answer, 18% are easy and 21% hard. It went down from 1.0 to 0.8 questions a shift since 2024.
- 06
The skill tested most is multi-step (52%), then application (37%).
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: 3 in 1 shift · 2020: 8 in 12 shifts · 2021: 18 in 24 shifts · 2022: 19 in 24 shifts · 2023: 6 in 12 shifts · 2024: 15 in 18 shifts · 2025: 8 in 8 shifts · 2026: 5 in 9 shifts.
- Up to 2023
- 1.0
- a shift, of 25
- Since 2024
- 0.8
- -0.2
- Usual gap
- 1.3 yrs
- between years asking it
- Shifts with it
- 70/108
- 65% of analysed shifts
Recent framings
- statement I/II on diazonium and alkene reactions
- identify compounds in reaction sequence
- deduce compound from reaction sequence
Revise first
- Reductive Ozonolysis Products · asked 2020, 2021, 2022, 2023, 2024, 2025, 2026
- Markovnikov's Rule Application · asked 2020, 2021, 2022, 2024, 2025, 2026
- Saytzeff vs. Hofmann Elimination · asked 2017, 2020, 2021, 2022, 2024, 2025
How it is asked
Difficulty, format and skill
Across all 82 questions on Alkenes and Alkynes since 2017.
Difficulty
QUESTIONS- Easy15 · 18%
- Medium50 · 61%
- Hard17 · 21%
Format
SHARE- Diagram based · 32 Q39%
- Single correct · 28 Q34%
- Numerical value · 13 Q16%
- Other · 5 Q6%
- Two statements · 2 Q2%
- Assertion–reason · 1 Q1%
- Match the list · 1 Q1%
Skill tested
SHARE- Multi-step · 43 Q52%
- Application · 30 Q37%
- Conceptual · 6 Q7%
- Recall · 2 Q2%
- Calculation · 1 Q1%
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 24 of the 46 ideas in this topic. 14 have never been asked yet.
- Asked directly24 · 52%
- Touched inside another question8 · 17%
- Never asked14 · 30%
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.
18 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
24 different ideas were tested; 14 came more than once.
deduce alkene from ozonolysis products
Diagram based · 16 shifts · 4 numericalpredict product of reaction sequence
Diagram based · 13 shifts · 1 numericalproduct mass from reaction sequence yield
Single correct · 6 shifts · 1 numericalpredict product of reaction
Single correct · 6 shiftspredict product of reaction
Diagram based · 4 shiftsidentify compounds in reaction sequence
Single correct · 4 shiftsmolar mass of product of reaction sequence
Diagram based · 4 shifts · 1 numericalpredict product of reaction
Diagram based · 3 shifts · 1 numericalcount stereoisomers of addition product
Single correct · 3 shifts · 1 numericalpredict product of reaction sequence
Diagram based · 3 shiftsidentify reagents in alkyne alkylation
Diagram based · 2 shiftspredict product of reaction sequence
Diagram based · 2 shiftsidentify alkene from oxidation products
Numerical value · 2 shifts · 1 numericalpredict product of reaction
Single correct · 2 shiftssp2 carbons in product of sequence
Numerical value · 1 shift · 1 numericalpredict product of reaction sequence
Single correct · 1 shiftcount pi electrons in products of bromination then substitution/elimination
Numerical value · 1 shift · 1 numericalpredict product of reaction
Single correct · 1 shiftpredict product of reaction
Diagram based · 1 shiftozonolysis products of hexene
Single correct · 1 shiftmajor alkene from alcohol dehydration with rearrangement
Diagram based · 1 shiftidentify compound from ozonolysis product test
Single correct · 1 shiftpredict product of reaction sequence
Diagram based · 1 shiftcount stereoisomers of halogen addition product
Numerical value · 1 shift · 1 numerical
| Idea | Years asked | Times | Shifts | Format | Numerical |
|---|---|---|---|---|---|
| Reductive Ozonolysis Productsdeduce alkene from ozonolysis products | 16 | 16 | Diagram basedMulti-step | 4 | |
| Markovnikov's Rule Applicationpredict product of reaction sequence | 13 | 13 | Diagram basedMulti-step | 1 | |
| Saytzeff vs. Hofmann Eliminationproduct mass from reaction sequence yield | 7 | 6 | Single correctApplication | 1 | |
| Hydroboration-Oxidationpredict product of reaction | 6 | 6 | Single correctMulti-step | – | |
| Carbocation Rearrangementspredict product of reaction | 5 | 4 | Diagram basedApplication | – | |
| Kucherov Alkyne Hydrationidentify compounds in reaction sequence | 4 | 4 | Single correctMulti-step | – | |
| Stereoselective Alkyne Reductionmolar mass of product of reaction sequence | 4 | 4 | Diagram basedApplication | 1 | |
| Allylic Halogenation with NBSpredict product of reaction | 3 | 3 | Diagram basedApplication | 1 | |
| Peroxide Effect (Anti-Markovnikov)count stereoisomers of addition product | 3 | 3 | Single correctMulti-step | 1 | |
| Halohydrin Formation Regiochemistrypredict product of reaction sequence | 3 | 3 | Diagram basedApplication | – | |
| Acetylide Ion Alkylationidentify reagents in alkyne alkylation | 2 | 2 | Diagram basedApplication | – | |
| Alkylation of Terminal Alkynespredict product of reaction sequence | 2 | 2 | Diagram basedMulti-step | – | |
| Oxidative Cleavage with Hot KMnO4identify alkene from oxidation products | 2 | 2 | Numerical valueApplication | 1 | |
| Oxymercuration-Demercurationpredict product of reaction | 2 | 2 | Single correctApplication | – | |
| Alkyne Hydroboration-Oxidationsp2 carbons in product of sequence | 1 | 1 | Numerical valueMulti-step | 1 | |
| Double Elimination to Alkynespredict product of reaction sequence | 1 | 1 | Single correctMulti-step | – | |
| Alkyne Synthesis via Double Eliminationcount pi electrons in products of bromination then substitution/elimination | 1 | 1 | Numerical valueMulti-step | 1 | |
| Hot KMnO4 Oxidative Cleavagepredict product of reaction | 1 | 1 | Single correctRecall | – | |
| Halohydrin Formation Regiochemistrypredict product of reaction | 1 | 1 | Diagram basedApplication | – | |
| Oxidative Ozonolysisozonolysis products of hexene | 1 | 1 | Single correctApplication | – | |
| Acid-Catalyzed Dehydration of Alcoholsmajor alkene from alcohol dehydration with rearrangement | 1 | 1 | Diagram basedApplication | – | |
| Alkyne Ozonolysisidentify compound from ozonolysis product test | 1 | 1 | Single correctMulti-step | – | |
| Cyclic Polymerization of Alkynespredict product of reaction sequence | 1 | 1 | Diagram basedMulti-step | – | |
| Halogenation Anti-Addition Stereochemistrycount stereoisomers of halogen addition product | 1 | 1 | Numerical valueMulti-step | 1 |
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
Alkenes and Alkynes questions, year by year
The newest 40 show their opening words as they appeared in the official paper; older ones name the idea they tested. Open one for its options and the official answer.
JEE Main 20265 questions in 5 shifts
- 4 Apr, Shift 1Q64An alkene (X) on ozonolysis followed by reduction gives following products. (2 moles), …
Idea: Reductive Ozonolysis Products
Asked the year beforeHardDiagram based · figure - 4 Apr, Shift 2Q64Compound (X) is subjected to the sequence of reactions as shown above. Molar mass of the major product (Y) formed is ________…
Idea: Stereoselective Alkyne Reduction
MediumDiagram based · figure - 5 Apr, Shift 1Q64"P" is a hydrocarbon of molecular formula:- . On ozonolysis, "P" forms "Q". "Q" on treatment with alkali under reflux…
Idea: Reductive Ozonolysis Products
Asked the year beforeHardDiagram based · figure - 6 Apr, Shift 1Q66Given below are two statements: Statement I: 3-phenylpropene reacts with HBr and gives secondary alkyl bromide having a chiral carbon atom…
Idea: Markovnikov's Rule Application
Asked the year beforeMediumTwo statements - 6 Apr, Shift 2Q65An optically active alkyl bromide , reacts with ethanolic KOH to form major compound [A] which reacts with bromine to…
Idea: Kucherov Alkyne Hydration
Asked the year beforeMediumSingle correct
JEE Main 20258 questions in 7 shifts
- 2 Apr, Shift 1Q66An optically active alkyl halide [A] reacts with hot KOH dissolved in ethanol and forms alkene [B] as major product…
Idea: Kucherov Alkyne Hydration
MediumSingle correct - 2 Apr, Shift 2Q75Consider the above sequence of reactions. 151 g of 2-bromopentane is made to react. Yield of major product P is 80% whereas Q is 100%.…
Idea: Saytzeff vs. Hofmann Elimination
Asked the year beforeMediumNumerical value · figure - 3 Apr, Shift 1Q65Which compound would give 3-methyl-6-oxoheptanal upon ozonolysis?
Idea: Reductive Ozonolysis Products
Asked the year beforeMediumDiagram based · figure - 4 Apr, Shift 2Q65Consider the following molecule (X). The structure of X is [figure: tricyclic fused polycyclic hydrocarbon (X) containing a cyclopentene…
Idea: Markovnikov's Rule Application
Asked the year beforeHardDiagram based · figure - 7 Apr, Shift 1Q67Given below are two statements: Statement I: Ozonolysis followed by treatment with Zn, of cis-2-butene gives ethanal.…
Idea: Reductive Ozonolysis Products
Asked the year beforeMediumTwo statements - 7 Apr, Shift 2Q66The number of optically active products obtained from the complete ozonolysis of the given compound is :…
Idea: Reductive Ozonolysis Products
Asked the year beforeMediumOther · figure - 7 Apr, Shift 2Q75Identify the structure of the final product (D) in the following sequence of the reactions :…
Idea: Alkyne Hydroboration-Oxidation
New ideaMediumNumerical value · figure - 8 Apr, Shift 2Q651,2-dibromocyclooctane …
Idea: Double Elimination to Alkynes
New ideaMediumSingle correct · figure
JEE Main 202415 questions in 11 shifts
- 4 Apr, Shift 1Q77Identify the correct set of reagents or reaction conditions 'X' and 'Y' in the following set of transformation.…
Idea: Markovnikov's Rule Application
EasyOther - 4 Apr, Shift 2Q75In the above chemical reaction sequence "A" and "B" respectively are
Idea: Reductive Ozonolysis Products
Asked the year beforeMediumDiagram based · figure - 4 Apr, Shift 2Q79Product 'A' Product A Product "B" Product A…
Idea: Hydroboration-Oxidation
Asked the year beforeEasySingle correct - 5 Apr, Shift 2Q77Identify the major product in the following reaction. 1-bromo-1-methylcyclopentane…
Idea: Saytzeff vs. Hofmann Elimination
EasyDiagram based · figure - 5 Apr, Shift 2Q79Consider the given chemical reaction : cyclohexene Product "A" Product "A" is :
Idea: Hot KMnO4 Oxidative Cleavage
New ideaEasySingle correct · figure - 6 Apr, Shift 1Q88The major product of the following reaction is P. …
Idea: Stereoselective Alkyne Reduction
MediumNumerical value · figure - 6 Apr, Shift 1Q89The major products from the following reaction sequence are product A and product B. [figure: cyclohexene; upper arrow to the right (i)…
Idea: Alkyne Synthesis via Double Elimination
New ideaHardNumerical value · figure - 9 Apr, Shift 1Q76Identify the product A and product B in the following set of reactions. [figure: …
Idea: Hydroboration-Oxidation
Asked the year beforeEasySingle correct · figure - 1 Feb, Shift 2Q75In the given reactions identify A and B [figure: alkene with (upper left) and…
Idea: Stereoselective Alkyne Reduction
EasyOther · figure - 27 Jan, Shift 1Q903-Methylhex-2-ene on reaction with HBr in presence of peroxide forms an addition product (A). The number of possible stereoisomers for 'A'…
Idea: Peroxide Effect (Anti-Markovnikov)
MediumNumerical value - 29 Jan, Shift 1Q74Identify product A and product B :
Idea: Allylic Halogenation with NBS
MediumDiagram based · figure - 29 Jan, Shift 1Q89[figure: trans-2-butene drawn as CH and H on the left carbon, H and CH on the right carbon (CH top-left, H bottom-left, H…
Idea: Reductive Ozonolysis Products
Asked the year beforeEasyNumerical value · figure - 30 Jan, Shift 1Q72Compound A formed in the following reaction reacts with B gives the product C. Find out A and B.…
Idea: Acetylide Ion Alkylation
EasyOther · figure - 31 Jan, Shift 1Q76The product (C) in the below mentioned reaction is :…
Idea: Markovnikov's Rule Application
EasySingle correct - 31 Jan, Shift 2Q75Major product of the following reaction is -
Idea: Markovnikov's Rule Application
HardDiagram based · figure
JEE Main 20236 questions in 6 shifts
- 6 Apr, Shift 2Q75In the following reaction, 'B' is
Idea: Carbocation Rearrangements
HardDiagram based · figure - 8 Apr, Shift 1Q89Molar mass of the hydrocarbon (X) which on ozonolysis consumes one mole of per mole of (X) and gives one mole each of…
Idea: Reductive Ozonolysis Products
Asked the year beforeMediumNumerical value - 8 Apr, Shift 2Q71Major product 'P' formed in the following reaction is: [reaction: (pent-4-enoic acid, drawn as…
Idea: Halohydrin Formation Regiochemistry
New ideaMediumDiagram based · figure - 10 Apr, Shift 2Q75Incorrect method of preparation for alcohols from the following is:
Idea: Hydroboration-Oxidation
Asked the year beforeEasySingle correct - 12 Apr, Shift 1Q75[figure: 2-hexene --(i) , (ii) --> Products] The two products formed in above reaction are -
Idea: Oxidative Ozonolysis
New ideaEasySingle correct · figure - 15 Apr, Shift 1Q76The product formed in the following multistep reaction is : …
Idea: Hydroboration-Oxidation
Asked the year beforeMediumOther · figure
JEE Main 202219 questions in 17 shifts
- 25 Jul, Shift 1Q73A compound 'A' on reaction with 'X' and 'Y' produces the same major product but different by product 'a' and 'b'. Oxidation of 'a' gives a…
Idea: Reductive Ozonolysis Products
Asked the year beforeMediumSingle correct · figure - 25 Jul, Shift 2Q73Major product of the following reaction is [figure: skeletal drawing, left to right: a C=C double bond at the left end whose inner carbon…
Idea: Markovnikov's Rule Application
Asked the year beforeMediumDiagram based · figure - 27 Jul, Shift 2Q73Major product ‘B’ of the following reaction sequence is : A…
Idea: Halohydrin Formation Regiochemistry
Asked the year beforeHardDiagram based · figure - 28 Jul, Shift 1Q73Choose the correct option for the following reactions. (3,3-dimethylbut-1-ene, drawn as…
Idea: Oxymercuration-Demercuration
New ideaMediumSingle correct · figure - 29 Jul, Shift 1Q73Which among the following pairs of the structures will give different products on ozonolysis ? (Consider the double bonds in the…
Idea: Reductive Ozonolysis Products
Asked the year beforeHardDiagram based · figure - 30 Jul, Shift 2Q60Among the following, how many hydrocarbon (s) with formula which on reaction with acidic potassium permagenate…
Idea: Oxidative Cleavage with Hot KMnO4
New ideaHardNumerical value · figure - 24 Jun, Shift 1 · Q90Markovnikov's Rule ApplicationAsked the year beforeHard
- 24 Jun, Shift 2 · Q75Hydroboration-OxidationMedium
- 25 Jun, Shift 1 · Q73Markovnikov's Rule ApplicationAsked the year beforeMedium
- 25 Jun, Shift 1 · Q75Saytzeff vs. Hofmann EliminationAsked the year beforeEasy
- 25 Jun, Shift 2 · Q75Halohydrin Formation RegiochemistryAsked the year beforeHard
- 26 Jun, Shift 2 · Q73Oxymercuration-DemercurationNew ideaMedium
- 27 Jun, Shift 1 · Q74Reductive Ozonolysis ProductsAsked the year beforeMedium
- 27 Jun, Shift 2 · Q73Alkylation of Terminal AlkynesMedium
- 28 Jun, Shift 1 · Q73Markovnikov's Rule ApplicationAsked the year beforeMedium
- 28 Jun, Shift 2 · Q74Acid-Catalyzed Dehydration of AlcoholsNew ideaMedium
- 28 Jun, Shift 2 · Q89Allylic Halogenation with NBSAsked the year beforeMedium
- 29 Jun, Shift 1 · Q73Oxidative Cleavage with Hot KMnO4New ideaMedium
- 30 Jun, Shift 1 · Q89Reductive Ozonolysis ProductsAsked the year beforeHard
JEE Main 202118 questions in 16 shifts
- 4 Aug, Shift 1 · Q43Stereoselective Alkyne ReductionNew ideaEasy
- 4 Aug, Shift 2 · Q42Reductive Ozonolysis ProductsAsked the year beforeMedium
- 26 Aug, Shift 1 · Q43Markovnikov's Rule ApplicationAsked the year beforeMedium
- 26 Aug, Shift 2 · Q60Reductive Ozonolysis ProductsAsked the year beforeMedium
- 27 Aug, Shift 1 · Q42Acetylide Ion AlkylationNew ideaMedium
- 31 Aug, Shift 1 · Q44Halohydrin Formation RegiochemistryNew ideaMedium
- 31 Aug, Shift 2 · Q41Saytzeff vs. Hofmann EliminationAsked the year beforeMedium
- 24 Feb, Shift 1 · Q41Carbocation RearrangementsAsked the year beforeMedium
- 24 Feb, Shift 1 · Q44Carbocation RearrangementsAsked the year beforeMedium
- 24 Feb, Shift 2 · Q44Kucherov Alkyne HydrationAsked the year beforeEasy
- 25 Feb, Shift 1 · Q44Markovnikov's Rule ApplicationAsked the year beforeMedium
- 26 Feb, Shift 1 · Q42Cyclic Polymerization of AlkynesNew ideaMedium
- 25 Jul, Shift 1 · Q42Reductive Ozonolysis ProductsAsked the year beforeMedium
- 25 Jul, Shift 2 · Q60Halogenation Anti-Addition StereochemistryNew ideaMedium
- 16 Mar, Shift 2 · Q43Alkyne OzonolysisNew ideaMedium
- 16 Mar, Shift 2 · Q44Allylic Halogenation with NBSNew ideaMedium
- 17 Mar, Shift 1 · Q43Carbocation RearrangementsAsked the year beforeMedium
- 17 Mar, Shift 2 · Q45Markovnikov's Rule ApplicationAsked the year beforeEasy
JEE Main 20208 questions in 7 shifts
- 8 Jan, Shift 2 · Q42Reductive Ozonolysis ProductsNew ideaMedium
- 8 Jan, Shift 2 · Q45Hydroboration-OxidationNew ideaMedium
- 9 Jan, Shift 1 · Q43Kucherov Alkyne HydrationNew ideaMedium
- 9 Jan, Shift 2 · Q43Markovnikov's Rule ApplicationNew ideaHard
- 2 Sep, Shift 1 · Q41Carbocation RearrangementsNew ideaHard
- 2 Sep, Shift 2 · Q44Saytzeff vs. Hofmann EliminationAsked the year beforeHard
- 4 Sep, Shift 2 · Q44Alkylation of Terminal AlkynesNew ideaHard
- 6 Sep, Shift 2 · Q30Peroxide Effect (Anti-Markovnikov)Asked the year beforeMedium
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.