Concept explainers
(a)
Interpretation:
Enthalpy change for the given reaction should be calculated and has to be labelled as endothermic or exothermic. The given reaction is,
Concept introduction:
Enthalpy
The value of standard enthalpy change
Where,
n is the number of moles.
(a)
Answer to Problem 5.81QE
Enthalpy change is
Explanation of Solution
The balanced equation for the given reaction follows as,
Standard enthalpy of formation values is given below,
Change in enthalpy can be calculated by the equation:
Substitute the values as follows,
The sign of enthalpy change is positive. Hence, it is an endothermic reaction.
(b)
Interpretation:
Enthalpy change for the given reaction should be calculated and has to be labelled as endothermic or exothermic. The given reaction is,
Concept introduction:
Refer to (a).
(b)
Answer to Problem 5.81QE
Enthalpy change is
Explanation of Solution
The balanced equation for the given reaction follows as,
Standard enthalpy of formation values is given below,
Change in enthalpy can be calculated by the equation:
Substitute the values as follows,
The sign of enthalpy change is negative. Hence, it is an exothermic reaction.
(c)
Interpretation:
Enthalpy change for the given reaction should be calculated and has to be labelled as endothermic or exothermic. The given reaction is,
Concept introduction:
Refer to (a).
(c)
Answer to Problem 5.81QE
Enthalpy change is
Explanation of Solution
The balanced equation for the given reaction follows as,
Standard enthalpy of formation values is given below,
Change in enthalpy can be calculated by the equation:
Substitute the values as follows,
The sign of enthalpy change is negative. Hence, it is an exothermic reaction.
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Chapter 5 Solutions
Chemistry: Principles and Practice
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