( I ) The bond dissociation energy of Fluorine is less than Bromine.
( II) In Fluorine molecule, lone pair-lone pair electronic repulsions and appreciable due to small size of Fluorine.

see full answer

Start JEE / NEET / Foundation preparation at rupees 99/day !!

21% of IItians & 23% of AIIMS delhi doctors are from Sri Chaitanya institute !!

An Intiative by Sri Chaitanya

I and II are true

I is true II is false

I is false and II is true

I and II are false

answer is A.

(Unlock A.I Detailed Solution for FREE)

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test

Detailed Solution

Bond lengths of halogens are in the order : F₂ < Cl₂< Br₂ < I₂.
Bond energies are expected in the order : F₂ > Cl₂ > Br₂ > Cl₂.
But the experimental bond enthalpies are : Cl₂ > Br₂ > F₂ > I₂.
Bond enthalpy of F₂ is very less, because lone pair - lone pair repulsions are appreciable in F₂ as the bond length is small in F₂.
It was also thought, though not appropriate, that F–F bond is weak as multiple bond is not possible with no d-orbitals in the valence shell of fluorine.