(a)
Interpretation:
Enthalpy change for the photosynthesis of glucose 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 5.80QE
Enthalpy change is
Explanation of Solution
The balanced equation for the photosynthesis of glucose 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 positive. Hence, it is an endothermic reaction.
(b)
Interpretation:
Enthalpy change for the reduction of iron (III) oxide with carbon should be calculated and has to be labelled as endothermic or exothermic.
Concept introduction:
Refer to (a).
(b)
Answer to Problem 5.80QE
Enthalpy change is
Explanation of Solution
The balanced equation for the reduction of iron (III) oxide with carbon 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 positive. Hence, it is an endothermic reaction.
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Chapter 5 Solutions
Chemistry: Principles and Practice
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