JEE Main · Chemistry · Aldehydes, Ketones and Carboxylic Acids
Aldol and Cannizzaro: JEE Main previous year questions
26 questions in the 108 JEE Main shifts Lumi analysed, in 7 of 8 years. Pattern: Asked most years. 9 came in 2024–26. Here is how it is asked and which ideas come back.
- Questions
- 26
- in 25 of 108 shifts
- Years asked
- 7/8
- last asked 2026
- Weighted estimate
- 0.2
- model; history: 0.2 a shift on average, typically 0.1–0.3
Key findings
- 01
Asked in 7 of 8 years with analysed shifts and in 25 of 108 shifts: 26 questions, #120 of 196 topics.
- 02
42% of its questions since 2020 tested an idea no earlier year had asked; 10 repeated an idea from the year before.
- 03
The most repeated idea is Intramolecular Aldol, asked 5 times in 5 shifts (2020, 2021, 2022, 2023, 2025), most often as “predict product of reaction”.
- 04
JEE Main has asked 9 of the 40 ideas in this topic; 29 have never been asked, directly or inside another question.
- 05
Mostly asked as diagram based (50%); 12% need a numerical answer, 8% are easy and 15% hard.
- 06
The skill tested most is application (50%), then multi-step (35%).
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: 0 in 1 shift · 2020: 2 in 12 shifts · 2021: 8 in 24 shifts · 2022: 6 in 24 shifts · 2023: 1 in 12 shifts · 2024: 4 in 18 shifts · 2025: 3 in 8 shifts · 2026: 2 in 9 shifts.
- Up to 2023
- 0.1
- a shift, of 25
- Since 2024
- 0.3
- 0.1
- Usual gap
- 1.0 yrs
- between years asking it
- Shifts with it
- 25/108
- 23% of analysed shifts
How it is asked
Difficulty, format and skill
Across all 26 questions on Aldol and Cannizzaro since 2017.
Difficulty
QUESTIONS- Easy2 · 8%
- Medium20 · 77%
- Hard4 · 15%
Format
SHARE- Diagram based · 13 Q50%
- Single correct · 6 Q23%
- Numerical value · 3 Q12%
- Two statements · 2 Q8%
- Other · 2 Q8%
Skill tested
SHARE- Application · 13 Q50%
- Multi-step · 9 Q35%
- Conceptual · 3 Q12%
- Calculation · 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 9 of the 40 ideas in this topic. 29 have never been asked yet.
- Asked directly9 · 23%
- Touched inside another question2 · 5%
- Never asked29 · 73%
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
Idea, year, question
Every idea JEE Main tested in this topic, with its eight years. Open one to read the questions.
- 30 Jan ’24 S2 · Q78m-chlorobenzaldehyde on treatment with 50% KOH solution yields
easyDiagram based
- 28 Jun ’22 S1 · Q74The correct structure of product ‘A’ formed in the following reaction,…
mediumDiagram basedAsked the year before
- 4 Aug ’21 S2 · Q45Cannizzaro reaction cannot be given by
easyOtherAsked the year before
- 31 Aug ’21 S2 · Q44For the reaction given below : [benzene ring drawn with an inner circle; CHO attached at top, attached at bottom] 1.…
mediumDiagram basedAsked the year before
- 3 Sep ’20 S2 · Q44The compound A in the following reactions is : A…
hardDiagram basedNew idea
- 30 Jan ’24 S2 · Q78
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
9 different ideas were tested; 8 came more than once.
predict product of reaction
Single correct · 5 shiftspredict product of reaction
Diagram based · 5 shiftspredict product of reaction sequence
Diagram based · 4 shifts · 1 numericalpredict product of reaction sequence
Diagram based · 3 shiftsdeduce compound then predict base reaction product
Diagram based · 2 shiftsstatement i/ii on aldehyde reactions
Diagram based · 2 shiftscount pi bonds in dibenzalacetone
Numerical value · 2 shifts · 2 numericalidentify starting compound from reaction product
Diagram based · 2 shiftscrossed cannizzaro, williamson and hi cleavage sequence
Diagram based · 1 shift
| Idea | Years asked | Times | Shifts | Format | Numerical |
|---|---|---|---|---|---|
| Intramolecular Aldolpredict product of reaction | 5 | 5 | Single correctApplication | – | |
| Cannizzaro Reactionpredict product of reaction | 5 | 5 | Diagram basedApplication | – | |
| Self-Aldol Condensationpredict product of reaction sequence | 4 | 4 | Diagram basedApplication | 1 | |
| Cross-Aldol Condensationpredict product of reaction sequence | 3 | 3 | Diagram basedMulti-step | – | |
| Intramolecular Cannizzaro Reactiondeduce compound then predict base reaction product | 2 | 2 | Diagram basedApplication | – | |
| Alpha-Hydrogen Aciditystatement i/ii on aldehyde reactions | 2 | 2 | Diagram basedApplication | – | |
| Claisen-Schmidt Condensationcount pi bonds in dibenzalacetone | 2 | 2 | Numerical valueCalculation | 2 | |
| Haloform Interference with Aldolidentify starting compound from reaction product | 2 | 2 | Diagram basedApplication | – | |
| Cross-Cannizzaro Reactioncrossed cannizzaro, williamson and hi cleavage sequence | 1 | 1 | Diagram basedMulti-step | – |
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
Aldol and Cannizzaro 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 20262 questions in 2 shifts
- 2 Apr, Shift 2Q66An organic compound 'x' where molar ratio of C, O and H are equal, on treatment with 50% KOH under reflux followed by acidification…
Idea: Intramolecular Cannizzaro Reaction
Asked the year beforeMediumSingle correct - 6 Apr, Shift 2Q64'' is the product which is obtained by the hydrolysis of prop-1-yne in the presence of mercuric sulphate under dilute acidic medium at…
Idea: Self-Aldol Condensation
MediumSingle correct
JEE Main 20253 questions in 3 shifts
- 2 Apr, Shift 1Q68Given below are two statements : Statement (I) : Vanillin ([structure: benzene ring with -CHO, -OH para to CHO and -OCH3 ortho to OH])…
Idea: Alpha-Hydrogen Acidity
MediumTwo statements · figure - 3 Apr, Shift 2Q68The major product (P) in the following reaction is : P (Major Product)
Idea: Intramolecular Cannizzaro Reaction
New ideaMediumDiagram based · figure - 8 Apr, Shift 2Q68When [structure: , a skeletal zigzag chain with a methyl ketone at one end and an aldehyde (C=O…
Idea: Intramolecular Aldol
MediumSingle correct · figure
JEE Main 20244 questions in 4 shifts
- 4 Apr, Shift 1Q78Given below are two statements : Statements I : Acidity of -hydrogens of aldehydes and ketones is responsible for Aldol reaction.…
Idea: Cross-Aldol Condensation
MediumTwo statements - 5 Apr, Shift 2Q87In the Claisen-Schmidt reaction to prepare 351 g of dibenzalacetone using 87 g of acetone, the amount of benzaldehyde required is ________…
Idea: Claisen-Schmidt Condensation
New ideaMediumNumerical value - 8 Apr, Shift 2Q86Two moles of benzaldehyde and one mole of acetone under alkaline conditions using aqueous NaOH after heating gives as the major…
Idea: Claisen-Schmidt Condensation
New ideaMediumNumerical value - 30 Jan, Shift 2Q78m-chlorobenzaldehyde on treatment with 50% KOH solution yields
Idea: Cannizzaro Reaction
EasyDiagram based · figure
JEE Main 20231 question in 1 shift
- 12 Apr, Shift 1Q77[figure: -(zig-zag chain)- --, --> 'A' major Product] A in the above…
Idea: Intramolecular Aldol
Asked the year beforeMediumSingle correct · figure
JEE Main 20226 questions in 6 shifts
- 25 Jul, Shift 2Q74What is the major product of the following reaction ? [figure: skeletal drawing of a carbon chain with a branch point (two bond stubs on a…
Idea: Self-Aldol Condensation
Asked the year beforeMediumDiagram based · figure - 27 Jul, Shift 2Q72The structure of A in the given reaction is : [figure: R-C(=O)-CH3 treated with NaOH and CH3CH2-Br (drawn as zigzag line with Br); product…
Idea: Alpha-Hydrogen Acidity
New ideaMediumDiagram based · figure - 28 Jun, Shift 1Q74The correct structure of product ‘A’ formed in the following reaction,…
Idea: Cannizzaro Reaction
Asked the year beforeMediumDiagram based · figure - 28 Jun, Shift 2Q76Isobutyraldehyde on reaction with formaldehyde and gives compound ‘A’. Compound ‘A’ reacts with KCN and yields compound…
Idea: Cross-Aldol Condensation
Asked the year beforeHardDiagram based · figure - 29 Jun, Shift 2Q90In the given reaction, [figure: six-membered ring with a carbonyl oxygen (O double bonded to a ring carbon); reagents over the arrow: (i)…
Idea: Self-Aldol Condensation
Asked the year beforeMediumNumerical value · figure - 30 Jun, Shift 1Q76Which among the following will be the major product of the given reaction ? [structure: skeletal chain: a terminal bond to a C=O carbon (O…
Idea: Intramolecular Aldol
Asked the year beforeMediumDiagram based · figure
JEE Main 20218 questions in 7 shifts
- 4 Aug, Shift 2Q45Cannizzaro reaction cannot be given by
Idea: Cannizzaro Reaction
Asked the year beforeEasyOther · figure - 26 Aug, Shift 1Q45The major products formed in the following reaction sequence A and B are : [figure: hexagonal ring joined to a carbonyl carbon (C=O) which…
Idea: Haloform Interference with Aldol
New ideaMediumOther · figure - 27 Aug, Shift 1Q44The structure of the starting compound P used in the reaction given below is : P…
Idea: Haloform Interference with Aldol
New ideaMediumDiagram based · figure - 31 Aug, Shift 2Q44For the reaction given below : [benzene ring drawn with an inner circle; CHO attached at top, attached at bottom] 1.…
Idea: Cannizzaro Reaction
Asked the year beforeMediumDiagram based · figure - 26 Feb, Shift 2Q44Identify A in the given chemical reaction. [structure drawn: benzene ring with two adjacent substituents]…
Idea: Intramolecular Aldol
Asked the year beforeMediumDiagram based · figure - 26 Feb, Shift 2Q45Identify A in the following chemical reaction. [structure drawn: benzene ring with CHO at one position and at the…
Idea: Cross-Cannizzaro Reaction
New ideaHardDiagram based · figure - 25 Jul, Shift 1Q44[figure: 3,3-dimethylcyclopentanone (ketone C=O, gem-dimethyl on adjacent ring carbon) reacts with , NaOH to give 'P'…
Idea: Cross-Aldol Condensation
New ideaHardSingle correct · figure - 18 Mar, Shift 2Q46[figure: reaction scheme] Consider the above reaction, the product ‘X’ and ‘Y’ respectively are :
Idea: Self-Aldol Condensation
New ideaMediumDiagram based · figure
JEE Main 20202 questions in 2 shifts
- 9 Jan, Shift 2Q44In the following reaction A is : A…
Idea: Intramolecular Aldol
New ideaMediumSingle correct · figure - 3 Sep, Shift 2Q44The compound A in the following reactions is : A…
Idea: Cannizzaro Reaction
New ideaHardDiagram based · 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.