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Aldehydes, Ketones, and Carboxylic Acids — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryAldehydes, Ketones, and Carboxylic Acids3 Marks
Question
An unknown aldehyde ‘A’ on reacting with alkali gives a β-hydroxy aldehyde, which loses water to form an unsaturated aldehyde, 2-butenal. Another aldehyde ‘B’ undergoes disproportionation reaction in the presence of conc. alkali to form products C and D. C is an arylalcohol with the formula, $C_7H_8O$.
  1. Identify A and B.
  2. Write the sequence of reactions involved.
  3. Name the product, when ‘B’ reacts with zinc amalgam and hydrochloric acid.
✓

Answer

  1. A is $CH_3CHO$ (ethanal).
B is $C_6H_5CHO$ (benzaldehyde).
  1.  
  1. Toluene.

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