Using the data in Appendix 2, calculate the standard entropy changes for the following reactions at 25
Interpretation:
The standard entropy change for the given reactionsis to be calculated.
Concept introduction:
Entropy is the direct measurement of randomness or disorderness. Entropy is an extensive property. It is a state function.
Entropy of a system is a measure of how spread out or how dispersed the system’s energy is. Change in entropy of a system is the difference between the entropy of the final state and the entropy of theinitial state.
The entropy of the system and the entropy of the surroundings make up the entropy of the universe.
Entropy change of the reaction is the difference between the entropies of the reactants and products.
Mathematically, the entropy change can be represented as follows:
Here,
Answer to Problem 14QP
Solution:
a)
b)
c)
Explanation of Solution
a)
The standard entropy change for the reaction is calculated using the expression as follows:
Here,
The standard entropy change for the reaction is as follows:
From Appendix
Substitute
Therefore, the standard entropy change for this reaction is
b)
The standard entropy change for the reaction is calculated using the expression as follows:
Here,
The standard entropy change for the reaction is as follows:
From Appendix
Substitute,
Therefore, the standard entropy change for this reaction is
Given information: The reaction is as follows:
c)
The standard entropy change for the reaction is calculated using the expression as follows:
Here,
The standard entropy change of the reaction is as follows:
From Appendix
Substitute,
Therefore, the standard entropy change for this reaction is
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Chapter 18 Solutions
Chemistry
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