Concept explainers
(a)
Interpretation:
The enthalpy of combustion of propane, nonane, and hexadecane has to be predicted with help of graphical method.
Concept Introduction:
The amount of energy which is produced or absorbed during the reaction is the enthalpy change of a
(a)
Answer to Problem 124QRT
The enthalpy of combustion of propane
Explanation of Solution
The given data table is shown below.
Hydrocarbon | Formula | Enthalpy if combustion (kJ/mol) |
Butane | ||
Pentane | ||
Hexane | ||
Heptane | ||
Octane |
The graph has been plotted between enthalpy of combustion on the
Figure 1
When the number of carbon atom is
Therefore, the enthalpy of combustion of propane
When the number of carbon atom is
Therefore, the enthalpy of combustion of nonane
When the number of carbon atom is
Therefore, the enthalpy of combustion of hexadecane
(b)
Interpretation:
The reason as to why the slope of graph enthalpy of combustion on the
Concept Introduction:
Refer to part (a).
(b)
Answer to Problem 124QRT
The graph has positive slope because bond enengy increases as the number of carbon increases.
Explanation of Solution
The given data table is shown below.
Hydrocarbon | Formula | Enthalpy if combustion (kJ/mol) |
Butane | ||
Pentane | ||
Hexane | ||
Heptane | ||
Octane |
The graph has been plotted between enthalpy of combustion on the
Figure 1
This graph has positive value.
The combustion of hydrocarbons involves breaking of
The bond enthalpy for
The bond enthalpy for
The number of bonds
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Chapter 10 Solutions
OWLv2 for Moore/Stanitski's Chemistry: The Molecular Science, 5th Edition, [Instant Access], 1 term (6 months)
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