Concept explainers
(a)
Interpretation:
Heat evolved by the given reaction at given condition has to be determined.
Concept introduction:
Bond energy or more correctly the bond dissociation enthalpy is the enthalpy change when breaking a bond in a molecule with the reactant and products in the gas phase.
Enthalpy of formation:
(a)
Explanation of Solution
Given data:
The balanced equation when n=1 is given below:
Bonds broken:
Bonds formed:
The total energy change is given below:
(b)
Interpretation:
Reason for having more or less energy is given off per mole in the formation of larger hydrocarbons has to be given without doing any calculation.
Concept introduction:
Bond dissociation enthalpy:
Bond energy or more correctly the bond dissociation enthalpy is the enthalpy change when breaking a bond in a molecule with the reactant and products in the gas phase.
Enthalpy of formation:
(b)
Explanation of Solution
Given data:
The balanced equation when n=1 is given below:
The given reaction is
From the equation it is clear that there will always be n
By combining all these terms, it is clear that as n becomes larger, more and more energy will be released.
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Chapter 4 Solutions
Chemistry in Context
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