Interpretation:
The molar enthalpy of vaporization and boiling point of octane has to be determined.
Concept Introduction:
Clausius-Clapeyron equation:
From this relationship we can calculate the molar enthalpy of vaporization by knowing the corresponding temperature and pressure values.
If we have pressures at two different temperatures, then enthalpy of vaporization can be calculated by
Boiling point of a liquid: The temperature at which external pressure and vapour pressure of the liquid become same.
Normal boiling point: When the external pressure is
Answer to Problem 22PS
The molar enthalpy of vaporization is
The boiling point of octane is calculated is
Explanation of Solution
Given:
Temperatures and corresponding pressures are given. We can calculate the molar enthalpy of vaporization by using the Clausius-Clapeyron equation
- The molar enthalpy of vaporization is calculated using given data.
Substituting the values
The molar enthalpy of vaporization is
- The boiling point is calculated by using given data
Normal boiling point is the temperature when the external pressure is
Substituting the values
The boiling point of octane is calculated is
The molar enthalpy of vaporization and boiling point of octane was determined.
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Chapter 11 Solutions
Chemistry & Chemical Reactivity
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