Concept explainers
(a)
Interpretation:
The reason behind less volatility of hexane than diethyl ether has to be described.
(a)
Explanation of Solution
Figure 1
Vapour pressure of a liquid is defined as the pressure of the vapour when liquid and vapour are in dynamic equilibrium. It increases with increase in temperature and a liquid with stronger intermolecular force of attractions has a lower vapour pressure at a given temperature.
If a liquid is less volatile, then it must have a lower vapour pressure which can be accounted for its stronger intermolecular force of attraction. Examining the above figure, it can be concluded that hexane has a lower vapour pressure than diethyl ether at any temperature. The non-covalent intermolecular forces of attraction acting between the molecules of hexane is London forces while in diethyl ether they are dipole-dipole forces and London forces. Because liquid hexane has a lower vapour pressure, it can be predicted that the larger hexane molecules experience larger collective intermolecular London forces than diethyl ether.
So due to this reason, hexane is less volatile than diethyl ether.
(b)
Interpretation:
The temperature at which 1- butanol have a pressure of
(b)
Answer to Problem ISP
The temperature of 1-butanol at
Explanation of Solution
Figure 2
Examine the above figure carefully. Draw a horizontal line from
(c)
Interpretation:
The reason why the boiling point of 1-butanol is greater than that of water has to be described.
(c)
Explanation of Solution
The liquid having greater boiling point means it has stronger collective intermolecular forces. Both water and 1-butanol can experience hydrogen bonding interactions. Water is a small molecule with a total of
(c)
Interpretation:
The substance which would evaporate immediately and which would remain as liquid has to be determined.
(c)
Explanation of Solution
Figure 3
The boiling point of diethyl ether is
(d)
Interpretation:
The
Concept Introduction:
Clausius-Clapeyron equation:
Where,
P1 and P2 are two sets of pressures and T1 and T2 are two sets of absolute temperatures.
R is universal gas constant.
(d)
Answer to Problem ISP
The
Explanation of Solution
Given data:
The normal boiling point of 1-butanol is
Clausius-Clapeyron equation:
Substituting all the data in the above equation and solving for
Therefore, the
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Chapter 9 Solutions
OWLv2 for Moore/Stanitski's Chemistry: The Molecular Science, 5th Edition, [Instant Access], 1 term (6 months)
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