The bond dissociation energy is highest for
Show Hint
When comparing bond dissociation energies:
• Consider bond length: shorter bonds generally have higher bond energy.
• Check for lone pair-lone pair repulsions, which can weaken bonds, as seen in F2.
Cl2
I2
F2
Br2
The Correct Option is A
Solution and Explanation
- Bond dissociation energy is the energy required to break a bond in a molecule. - The bond energy order for halogens is:
\(Cl_2 > Br_2 > F_2 > I_2.\)
- Although F2 has a shorter bond length than Cl2, the bond energy of F2 is lower due to lone pair-lone pair repulsions. - Cl2 has the highest bond dissociation energy as it has the optimal bond length and no significant repulsions.
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