Given below are the bond dissociation energy (BDE; kJ mol^-1) values. Based on the data, the correct statement about the following equilibrium is

Bond	BDE (kJ mol-1)	Bond	BDE (kJ mol-1)
O-H	-460	C-C	-360
C-H	-420	C=O	-760
C-O	-380	C=C	-630

Concept:

Keto-enol tautomerism is a dynamic equilibrium between two constitutional isomers, called tautomers, that involve the migration of a hydrogen atom and the rearrangement of double bonds in a molecule. These tautomers interconvert rapidly under normal conditions, and the equilibrium is influenced by factors such as the nature of substituents, solvent, and temperature.

Explanation:

• Keto-Enol Tautomerization

In keto-enol tautomerism, the keto tautomer is usually more stable than enol tautomer and is more preferred. Hence, A>B.

• Bond Dissociation Energy Calculation​

​→ Types of bonds present in keto form are 1 C=O, 2 C-C, 6 C-H

Therefore, total BDE for keto tautomer is

BDE = 1X(C= O) + 2X(C-C) + 6X(C-H)

BDE = 1X( -760 ) + 2X (-360) + 6X (-420)

BDE = -4000 kJ mol^-1.

→Types of bonds present in enol form are 1 O-H, 1 C-O, 1 C-C, 1C=C, 5 C-H.

Therefore, total BDE for enol tautomer is

BDE = 1X (O-H) + 1X (C-O) + 1X (C-C) + 1X (C=C) + 5X(C-H)

BDE = 1X (-460) + 1X (-380) + 1X(-360) + 1X (-630) + 5X(-420)

BDE = -3930 kJ mol ^-1.

Hence, keto form is more stable than enol form by 70 kJ mol^-1.

Conclusion:

Keto tautomer is more stable than enol tautomer by 70 kJ mol^-1.