Interpretation:
The equilibrium pressure constant and temperature for the given reaction is to be calculated.
Concept introduction:
All the energy available with the system, utilized in doing useful work, is called Gibbs free energy.
Entropy is the direct measurement of randomness or disorder. It is an extensive property and a state function.
The enthalpy of the system defined as the sum of the internal energy and the product of the pressure and the volume. It is a state function and an extensive property.
The standard Gibbs free energy change for the given reaction at temperature is calculated using the following expression:
The standard enthalpy change of the reaction,
The standard entropy change for this reaction is calculated using the following expression:
The equilibrium pressure constant is calculated using expression as follows:
Answer to Problem 98QP
Solution: The equilibrium pressure constant for the given reaction is
At a temperature higher than
and
Explanation of Solution
Given information: The reaction is as follows:
Temperature,
The equation for the reaction of
The standard Gibbs free energy change for the given reaction at temperature
Here,
The standard enthalpy change of the system,
The standard enthalpy change of the reaction,
Here,
The enthalpy change for the reaction is as follows:
From appendix
Substitute the standard enthalpy change of the formation value of the substance in the above expression.
Therefore, the standard enthalpy changes for the given reaction are
The entropy change of the system,
The standard entropy change for this reaction is calculated using the following expression:
Here,
The entropy change for the reaction is as follows:
From appendix2, the standard entropy values of the substances are as follows:
Substitute the standard entropy values of the substances in the above expression.
Therefore, the standard entropy change for the given reaction is
The standard Gibbs free energy change for the given reaction at temperature
Here,
Substitutes the value of
Therefore, standard Gibbs free energy change for the given reaction is
The equilibrium pressure constant is calculated using expression as follows:
Here,
is the constant,
is the temperature,
Substitute the value of
Therefore, the equilibrium pressure constant for the given reaction is
Entropy change for this reaction is negative. The Gibbs free energy is positive at higher temperature.
The temperature is calculated using the following expression:
Here,
Substitute the value of
Therefore,
will be smaller than one. The reaction moves in the backward direction. The temperature higher than
On adding a catalyst to the reaction, the value of
The equilibrium pressure constant for the given reaction is
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Chapter 18 Solutions
Chemistry
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