Chapter 5, Problem 5.117AP

(a)

Interpretation Introduction

Interpretation: The standard enthalpy of formation of liquid water is given to be $-285.8\text{kJ}/\text{mol}$. The significance of the negative sign associated with the given value is to be stated.

The large magnitude of given value than the enthalpy of vaporization of water $\left(\Delta H_{\text{vap}}^{\text{ο}}=40.67\text{kJ}/\text{mol}\right)$ is to be explained.

The amount of heat produced for the given data is to be calculated.

Concept introduction: In exothermic process heat is evolved and the sign of enthalpy of formation is in negative.

The intermolecular bonds are too stronger than intra molecular bonds.

The amount of heat $\left(q\right)$ produced for the formation of liquid water is calculated by the formula,

$q=n\times \Delta H_{\text{f}}^{\text{ο}}$

To determine: The significance of the negative sign associated with the given value.

(b)

Interpretation Introduction

To determine: The explanation for large magnitude of given value than the enthalpy of vaporization of water $\left(\Delta H_{\text{vap}}^{\text{ο}}=40.67\text{kJ}/\text{mol}\right)$.

(c)

Interpretation Introduction

To determine: The amount of heat produced for the given data.