Chapter 21, Problem 79GQ

Interpretation Introduction

Interpretation:

To calculate the average $\text{O}-\text{F}$ bond enthalpy in ${\text{OF}}_{\text{2}}$ molecule.

Concept introduction:

The bond dissociation energy is the energy required to break one mole of the gas (in a gaseous state) to give the separate atoms in a gaseous state. The bond dissociation energy is the energy of a single bond while bond energy is the average of the all bond dissociation energies. For the diatomic molecule bond dissociation energy is equal to the bond energy of the molecule.

The change of enthalpy to form one mole of a substance from its constituent elements when all the substances in the standard form is known as standard enthalpy of formation.

The standard enthalpy of formation $\left({\Delta }_f{\text{H}}^{\circ }\right)$ in terms of standard bond dissociation enthalpy $\left({\text{B}}^{\circ }\right)$ is written as,

${\Delta }_f{\text{H}}^{\circ }={\displaystyle \sum {\text{B}}^{\circ }{}_{\text{products}}-{\displaystyle \sum {\text{B}}^{\circ }{}_{\text{reactants}}}}$ (1)