Chapter 10, Problem 10.83QP

Interpretation Introduction

Interpretation: Based on the molecular orbital theory, the difference between the bond enthalpies of ${\text{F}}_{\text{2}}$ molecule and ${\text{F}}_2^{-}$ ion has to be explained.

Concept Introduction:

Molecular orbital theory:

The interaction of atomic orbitals of the bonding atoms results in the formation of molecular orbitals which are associated to the entire molecule. The molecular orbitals describe the covalent bonding formed by the overlapping of atomic orbitals of two atoms.

Bond enthalpy:

Bond enthalpy is the amount of energy required to break one mole of a particular type of bond. Strong bond requires more energy for breaking it whereas weak bond requires  less energy for breaking it. So, bond enthalpy determines whether a bond is strong or weak. Hence, bond enthalpy decides the bond strength.

The bond order can be calculated as follows:

$\text{Bond}\text{order}\text{=}\frac{\left(\begin{array}{l}\text{Number}\text{of}\text{electrons}\text{in}\\ \text{bonding}\\ \text{molecular}\text{orbital}\end{array}\right)-\left(\begin{array}{l}\text{Number}\text{of}\text{electrons}\\ \text{in}\text{antibonding}\\ \text{molecular}\text{orbital}\end{array}\right)}{\text{2}}$