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.

Question

Observe the following reaction and same reaction is carried out with the following compound:

X and Y can be differentiated by:

Answer 1

To determine the correctness of the given statements, let's analyze them one by one with the relevant chemical concepts:

Statement I: Cross aldol condensation between two different aldehydes will always produce four different products.
- Explanation: Cross aldol condensation involves two different aldehydes reacting in the presence of a base to form β-hydroxyaldehydes, which can further dehydrate to form α,β-unsaturated aldehydes.
- When two different aldehydes (say Aldehyde A and Aldehyde B) are involved, the possible aldol reactions are:
  - Aldehyde A reacting with itself.
  - Aldehyde B reacting with itself.
  - Aldehyde A reacting with Aldehyde B.
  - Aldehyde B reacting with Aldehyde A (which is different due to possible stereoisomers).
- Thus, typically four different products can be formed depending on the conditions, making this statement true.
Statement II: When semicarbazide reacts with a mixture of benzaldehyde and acetophenone under optimum pH, it forms a condensation product with acetophenone only.
- Explanation: Semicarbazide forms semicarbazones with carbonyl compounds. It reacts preferentially with aldehydes over ketones because aldehydes are generally more reactive towards nucleophilic addition than ketones due to less steric hindrance and electronic factors.
- In a mixture of benzaldehyde (an aldehyde) and acetophenone (a ketone), semicarbazide would predominantly react with benzaldehyde to form benzaldehyde semicarbazone.
- Therefore, the statement that the condensation product forms with acetophenone only is false.

Conclusion: Based on the above analysis, Statement I is true but Statement II is false.

Answer 2

To determine the correctness of the given statements, let's analyze them one by one with the relevant chemical concepts:

Statement I: Cross aldol condensation between two different aldehydes will always produce four different products.
- Explanation: Cross aldol condensation involves two different aldehydes reacting in the presence of a base to form β-hydroxyaldehydes, which can further dehydrate to form α,β-unsaturated aldehydes.
- When two different aldehydes (say Aldehyde A and Aldehyde B) are involved, the possible aldol reactions are:
  - Aldehyde A reacting with itself.
  - Aldehyde B reacting with itself.
  - Aldehyde A reacting with Aldehyde B.
  - Aldehyde B reacting with Aldehyde A (which is different due to possible stereoisomers).
- Thus, typically four different products can be formed depending on the conditions, making this statement true.
Statement II: When semicarbazide reacts with a mixture of benzaldehyde and acetophenone under optimum pH, it forms a condensation product with acetophenone only.
- Explanation: Semicarbazide forms semicarbazones with carbonyl compounds. It reacts preferentially with aldehydes over ketones because aldehydes are generally more reactive towards nucleophilic addition than ketones due to less steric hindrance and electronic factors.
- In a mixture of benzaldehyde (an aldehyde) and acetophenone (a ketone), semicarbazide would predominantly react with benzaldehyde to form benzaldehyde semicarbazone.
- Therefore, the statement that the condensation product forms with acetophenone only is false.

Conclusion: Based on the above analysis, Statement I is true but Statement II is false.

Show Hint