Concept explainers
(a)
Interpretation:
To verify Trouton's rule for the given set of substances.
Concept Introduction:
According to Trouton's rule for, various liquids attheir boiling point the change in entropy value will be the same. The ratio of enthalpy of vaporization and boiling temperature of various liquids has the same value.
Where,
(a)
Answer to Problem 17.48QP
Trouton's rule is verified for benzene, hexane, mercury and toluene. All the four substances have
Explanation of Solution
To record the given data
To verify Trouton's rule for benzene
Trouton's rule can be verified by plugging in the values of
Since the value is approximately equal to
To verify Trouton's rule for hexane
Trouton's rule can be verified by plugging in the values of
Since the value is approximately equal to
To verify Trouton's rule for mercury
Trouton's rule can be verified by plugging in the values of
Since the value is approximately equal to
To verify Trouton's rule for Toluene
Trouton's rule can be verified by plugging in the values of
Since the value is approximately equal to
(b)
Interpretation:
To verify Trouton's rule for the given set of substances.
Concept Introduction:
According to Trouton's rule for, various liquids attheir boiling point the change in entropy value will be the same. The ratio of enthalpy of vaporization and boiling temperature of various liquids has the same value.
Where,
(b)
Answer to Problem 17.48QP
Trouton's rule is not obeyed by water and ethanol due to the high entropy of vaporization.
Explanation of Solution
To record the given data
To verify Trouton's rule for ethanol
Trouton's rule can be verified by plugging in the values of
Since, the value is greater than
To verify Trouton's rule for water
Trouton's rule can be verified by plugging in the values of
Since the value is greater than
To explain the reason for the deviation from hydrogen bond in case of water and ethanol.
For water and ethanol there exist strong hydrogen bonding attraction in the liquid state. Hydrogen bonding interaction decreases the entropy in the system. In gaseous state the hydrogen bonding interaction becomes weaker and the molecules will have more randomness in the system. The entropy of vaporization will be high. This is the reason why water and ethanol is showing larger deviation from Trouton's rule.
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Chapter 17 Solutions
CHEMISTRY STUD.SOL.MANUAL >C<
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