Explanation

Statement I :

Bond dissociation enthalpy among halogens follows:

Cl₂ > Br₂ > F₂ > I₂

Although F–F bond is shorter, it is weaker than Cl–Cl due to strong lone pair–lone pair repulsions in the small F atom.

Thus, the given order is correct.

Statement I is true.

Statement II :

According to Fajans’ rule, covalent character increases with:

• Higher charge on cation

• Smaller size of cation

SnCl₄ > SnCl₂ ✔ (Sn⁴⁺ has higher charge than Sn²⁺)

PbCl₄ > PbCl₂ ✔ (Pb⁴⁺ has higher charge than Pb²⁺)

For uranium fluorides:

UF₆ contains U⁶⁺ (higher charge)

UF₄ contains U⁴⁺ (lower charge)

Higher oxidation state means greater polarization and more covalent character.

Therefore,

UF₆ > UF₄

But statement given says UF₄ > UF₆, which is incorrect.

Statement II is false.

Hence, Statement I is true but Statement II is false.

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