Chapter 6, Problem 6.79P

Interpretation Introduction

Interpretation: The value of $\Delta H{°}_{\text{f}}$ of gaseous $\text{HCl}$ needs to be determined.

Concept introduction: $\Delta H{°}_{\text{f}}$ (standard heat of formation) is change in enthalpy for the formation of 1mol of any compounds from its constituent elements which are at their standard states (1 atm and $\text{25}\text{°}\text{C}$ ). $\Delta H{°}_{\text{rxn}}$ is the enthalpy change for any reaction in which reactants and products are at standard states (1 atm and $\text{25}\text{°}\text{C}$ ) .