(a)
Interpretation:
Enthalpy change for the fermentation of glucose to ethyl alcohol and carbon dioxide should be calculated and has to be labelled as endothermic or exothermic.
Concept introduction:
Enthalpy
The value of standard enthalpy change
Where,
n is the number of moles.
(a)
Answer to Problem 5.79QE
Enthalpy change is
Explanation of Solution
The balanced equation for the fermentation of glucose to ethyl alcohol and carbon dioxide is given 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.
(b)
Interpretation:
Enthalpy change for the combustion of normal butane should be calculated and has to be labelled as endothermic or exothermic.
Concept introduction:
Refer to (a).
(b)
Answer to Problem 5.79QE
Enthalpy change is
Explanation of Solution
The balanced equation for the combustion of normal butane is given 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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