Chapter 6, Problem 6.40P

(a)

Interpretation Introduction

Interpretation:

Using Le Chatelier’s principle and the value of ${\text{K}}_{\text{w}}$, whether the autoprotolysis of water is exothermic or endothermic at $\text{25°C}$ has to be explained.

Concept introduction:

Le Chatelier’s principle:

At equilibrium, the system is exposed to a change that distract the system.  This principle states that the direction in which the system taking back to equilibrium is like that the change is partially balance.

Enthalpy change $\left(\Delta H\right)$:

Enthalpy change for a reaction is either heat is released or absorbed by the system. If $\text{ΔH}$ is positive, the reaction is endothermic and the sign of $\text{ΔH}$ is v means the reaction is exothermic.

(b)

Interpretation Introduction

Interpretation:

Using Le Chatelier’s principle and the value of ${\text{K}}_{\text{w}}$, whether the autoprotolysis of water is exothermic or endothermic at $\text{100°C}$ has to be explained.

Concept introduction:

Le Chatelier’s principle:

At equilibrium, the system is exposed to a change that distract the system.  This principle states that the direction in which the system taking back to equilibrium is like that the change is partially balance.

Enthalpy change $\left(\Delta H\right)$:

Enthalpy change for a reaction is either heat is released or absorbed by the system. If $\text{ΔH}$ is positive, the reaction is endothermic and the sign of $\text{ΔH}$ is v means the reaction is exothermic.

(c)

Interpretation Introduction

Interpretation:

Using Le Chatelier’s principle and the value of ${\text{K}}_{\text{w}}$, whether the autoprotolysis of water is exothermic or endothermic at $\text{300°C}$ has to be explained.

Concept introduction:

Le Chatelier’s principle:

At equilibrium, the system is exposed to a change that distract the system.  This principle states that the direction in which the system taking back to equilibrium is like that the change is partially balance.

Enthalpy change $\left(\Delta H\right)$:

Enthalpy change for a reaction is either heat is released or absorbed by the system. If $\text{ΔH}$ is positive, the reaction is endothermic and the sign of $\text{ΔH}$ is v means the reaction is exothermic.