Chapter 8.13, Problem 1PPC

Interpretation Introduction

Interpretation:

Whether the reactions are endothermic or exothermic is to be determined.

Concept Introduction:

The chemical reaction in which energy is evolved is called exothermic reaction.

The chemical reaction in which energy is absorbed is called endothermic reaction.

The standard enthalpy for a reaction is the amount of enthalpy that is to occur at standard conditions.

The enthalpy of reaction can be calculated as:

$\Delta H{°}_{rxn}={\displaystyle \sum \text{BE}}\left(\text{reactants}\right)-{\displaystyle \sum \text{BE}}\left(\text{products}\right)$.

Here, BE (reactant)is the average value of bond enthalpy for reactants and BE (products) is the average value of bond enthalpy for products.

The bond enthalpy of triple bond is always more than the bond enthalpy of double bond.