Q. The bond dissociation energy of and follow the order

 2076  177 J & K CETJ & K CET 2006 Report Error

Solution:

As we move from top to bottom in halogen family the bond energy of the molecules decreases as the bond distance increases. As the bond distance increases it requires less energy to break the bond i.e. less bond energy.
So, the order of bond energy of the molecules is .