Chapter 8.10, Problem 1.1ACP

Interpretation Introduction

Interpretation: It should be identified that whether given reaction is an endothermic or exothermic step using bond enthalpy data.

Concept Introduction:

Exothermic reaction: Reaction is considered as exothermic if it releases energy in the form of heat.

Endothermic reaction: The reaction which requires energy and absorbs in order to complete the reaction.

Bond Dissociation Enthalpy${\Delta }_{r}H$: The change in enthalpy as bond break in molecule with reactants and products in gas phase. The bond breaking process is endothermic since it requires energy to break hence ${\Delta }_{r}H$ will be a positive value and the bond making process in a reaction is exothermic.

The reaction enthalpy change determined by using the following equation,

$\text{ΔrH = }\sum \text{ΔH}\left(\text{bonds}\text{broken}\right)\text{ - }\sum \text{ΔH}\left(\text{bonds}\text{formed}\right)$