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Isomerism · Question 10

JEE Main 2025 (Online) 7th April Evening ShiftMCQMedium📈 Topic in 10% papers+4−1
1

The number of optically active products obtained from the complete ozonolysis of the given compound is : [figure]

  1. 4
  2. 0
  3. 2
  4. 1

Answer

(2) 0

Solution

Ozonolysis (O3, then Zn/H2O) breaks each C=C into two C=O groups. The three C=C bonds give:

From both ends: CH3CHO (2 molecules)

From the middle part, each stereocentre ends up between two CHO groups:

OHC- CH3 |CH-CHO (2 molecules, 2-methylpropanedial)

In 2-methylpropanedial the central carbon carries H, CH3 and two identical –CHO groups, so it is not chiral; ethanal is also achiral.

Number of optically active products = 0

Answer: (2)

JEE Main 2025 (Online) 7th April Evening Shift

Keep practising — Isomerism

2

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

  1. Both Statement I and Statement II are correct
  2. Statement I is incorrect but Statement II is correct
  3. Both Statement I and Statement II are incorrect
  4. Statement I is correct but Statement II is incorrect
JEE Main 2025 (Online) 7th April Evening Shift
3

Identify the correct statements from the following. Choose the correct answer from the options given below:

  1. B & C Only
  2. C & D Only
  3. A,B & C Only
  4. A & B Only
JEE Main 2025 (Online) 3rd April Morning Shift
4

The total number of structural isomers possible for the substituted benzene derivatives with the molecular formula C9H12 is .

JEE Main 2025 (Online) 3rd April Evening Shift
5

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. Both Statement I and Statement II are true
  3. Statement I is true but Statement II is false
  4. Both Statement I and Statement II are false
JEE Main 2025 (Online) 28th January Evening Shift

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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