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JEE Main202624 January 2026Evening ShiftChemistryAldehydes and KetonesActual

Given below are two statements: Statement I : Cross aldol condensation between two different aldehydes will always produce four different products. Statement II : When semicarbazide reacts with a mixture of benzaldehyde and acetophenone under optimum pH, it forms a condensation product with acetophenone only. In the light of the above statements, choose the correct answer from the options given below

Options

  1. AStatement I is false but Statement II is true
  2. BBoth Statement I and Statement II are false
  3. CBoth Statement I and Statement II are true
  4. DStatement I is true but Statement II is false

Correct answer

B. Both Statement I and Statement II are false

Step-by-step solution

Statement I: Cross aldol condensation between two different aldehydes produces four products only if both aldehydes have -hydrogen atoms. If one aldehyde lacks -hydrogen (e.g., benzaldehyde and acetaldehyde), only two products are typically formed (one self and one cross). If neither has -hydrogen, no aldol condensation occurs. Thus, it does not 'always' produce four products. Statement I is false. Statement II: Benzaldehyde is an aldehyde and acetophenone is a ketone. Aldehydes are generally more reactive than ket

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