Calculate ΔS°(system), ΔS°(surroundings), and ΔS°(universe) for each of the following processes at 298 K, and comment on how these systems differ.
- (a) HNO3(g) → HNO3(aq)
- (b) NaOH(s) → NaOH(aq)
(a)
Interpretation:
The entropy change for the system, surroundings and universe for the given reaction should be calculated and commented how this system differs.
Concept introduction:
The universe consists of two parts, systems and surroundings. The entropy change for the universe is the sum of entropy change for the system and for surroundings.
The
The
The
Here,
Answer to Problem 40GQ
The
The
The
Explanation of Solution
The entropy change for the system, surroundings and universe for the given reaction is calculated below.
Given:
The Appendix L referred for the values of standard entropies and enthalpies.
The standard entropy of
The standard entropy of
The standard enthalpy of
The standard enthalpy of
The balanced chemical equation is:
The
Substituting the respective values
The
Substituting the respective values
The
Now,
The
The
The
The given reaction is exothermic. There is more decrease in entropy in formation of
(b)
Interpretation:
The entropy change for the system, surroundings and universe for the given reaction should be calculated and commented how this system differs.
Concept introduction:
The universe consists of two parts, systems and surroundings. The entropy change for the universe is the sum of entropy change for the system and for surroundings.
The
The
The
Here,
Answer to Problem 40GQ
The
The
The
Explanation of Solution
The entropy change for the system, surroundings and universe for the given reaction is calculated below.
Given:
The Appendix L referred for the values of standard entropies and enthalpies.
The standard entropy of
The standard entropy of
The standard enthalpy of
The standard enthalpy of
The balanced chemical equation is:
The
Substituting the respective values
The
Substituting the respective values
The
Now,
The
The
The
The given reactions is exothermic. The entropy change for the formation of
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Chapter 18 Solutions
Chemistry & Chemical Reactivity
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