Concept explainers
(a)
Interpretation:
The equation for the straight line using the given data has to be written.
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
(a)
Answer to Problem 66SCQ
The equation for straight line is
Explanation of Solution
Given:
2.30 | 0.00369 |
3.69 | 0.00342 |
4.61 | 0.00325 |
5.99 | 0.00297 |
6.63 | 0.00285 |
From the given data we can derive the equation for straight line
In the given graph
(b)
Interpretation:
The way by which enthalpy of vaporization can be calculated using the graph has to be given.
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
(b)
Answer to Problem 66SCQ
The explanation for determining enthalpy of vaporization from the graph is given.
Explanation of Solution
Given:
Temperature | Vapour Pressure |
287 | 1 |
326.8 | 10 |
357.3 | 40 |
381.3 | 100 |
424.4 | 400 |
Using the data given we get a straight line graph and it satisfies the straight line equation
In the graph the y axis have
The equation corresponding to the straight line in the graph is
From the slope of the graph we can calculate the molar enthalpy of vaporization.
From the graph drawn,
Thus from the graph we can calculate the slope and using the equation
(c)
Interpretation:
The vapour pressure of ethanol at
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
(c)
Answer to Problem 66SCQ
The vapour pressure of ethanol at
Explanation of Solution
We know the equation of the line. Substituting the given temperatures in this equation, we can calculate the vapour pressures.
Vapour pressure at
Vapour pressure at
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Chapter 11 Solutions
Chemistry & Chemical Reactivity
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