Question

Which of the following statement(s) is/are correct about tautomers?

• A. They possess different electronic and atomic arrangements
• B. They possess different electronic but same atomic arrangement
• C. They have different atomic arrangements but same electronic arrangement
• D. They exist in equilibrium

Answer 1

Answer: (B), (D)

The correct options are
B They possess different electronic but same atomic arrangement
D They exist in equilibrium

• Keto-enol tautomerization is chemical equilibrium between a keto form and enol form.
  
• The interconversion of two forms involved the movement of proton and the shifting of electrons.
  
• A compound containing a carbonyl group (C=O) is normally in rapid equilibrium with an enol tautomer, which contains a pair of double bonded carbon atoms adjacent to a hydroxyl (-OH).
• For a carbonyl compound to exhibit tautomerism, the essential condition is that it must have at least one alpha H atom.
  
• Among the given set of compounds (A and C) do not possess an alpha H, whereas compound (B, D) posses an alpha H.