Question

Which one of the following orders is not in accordance with the property stated against it? 

(a) F₂ > Cl₂ > Br₂ > I₂ : Bond dissociation energy 

(b) F₂ > Cl₂ > Br₂ > I₂ : Oxidising power 

(c) HI > HBr > HCl > HF : Acidic properly in water

(d) F₂ > Cl₂ > Br₂ > I₂: Electronegativity

Answer 1

The correct option is : (a) F₂ > Cl₂ > Br₂ > I₂ : Bond dissociation energy

Explanation:

The lower value of bond dissociation energy of fluorine is due to the high inter-electronic repulsion between non-bonding electrons in the 2p-orbitals of fluorine. As a result F - F bond is weaker in comparison to Cl - Cl and Br - Br bonds.