Chapter 24, Problem 24.10YT

Interpretation Introduction

Interpretation:

The given equation, which accounts for the changes in the numbers of $\text{C-C}$ and $\text{C=C}$ bonds, is to be solved and completed, and from this value, it is to be explained how this estimate of ${\text{ΔH}}_{{}_{\text{rxn}}}^{{}^{\text{°}}}$ compares to the experimentally measured value of $\text{-168}$ $\text{kJ/mol}$ ($\text{-40}$$\text{kcal/mol}$).

Concept introduction:

The average energy of $\text{C-C}$ is $\text{339 kJ/mol}$, and that of $\text{C=C}$ is $\text{619 kJ/mol}$. The change in enthalpy of the reaction (${\text{ΔH}}^{\text{o}}$) is calculated as ${\text{ΔH}}^{\text{o}}{\text{ = ΣH}}_{\text{products }}^{\text{o}}{\text{- ΣH}}_{\text{reactants}}^{\text{o}}$. The negative value of the ${\text{ΔH}}^{\text{o}}$ suggests that the given reaction is exothermic.