(a)
Interpretation: Standard enthalpy of the reaction and change in standard entropy of the given reaction are to be determined and the temperature at which the change in standard Gibb’s energy is zero, is to be calculated.
Concept introduction: The standard enthalpy of the reaction is calculated by the formula,
The change in standard Gipp’s free energy of the reaction is calculated as,
To determine: Standard enthalpy of the reaction and change in standard entropy of the given reaction.
(a)
Answer to Problem 95CWP
Standard enthalpy of the reaction and change in standard entropy of the given reaction is
Explanation of Solution
Hydrogen gas is produced by reacting graphite with water.
The standard enthalpy of formation of
The standard enthalpy of formation of
The standard enthalpy of formation of
The standard enthalpy of the reaction is calculated by the formula,
Therefore, the above equation becomes,
Substitute the value of
Therefore, the standard enthalpy of the reaction is
The standard entropy of
The standard entropy of
The standard entropy of
The standard entropy of
The standard entropy change of the reaction is calculated by the formula,
Therefore, the above equation becomes,
Substitute the value of
Therefore, the standard entropy change of the reaction is
(b)
Interpretation: Standard enthalpy of the reaction and change in standard entropy of the given reaction are to be determined and the temperature at which the change in standard Gibb’s energy is zero, is to be calculated.
Concept introduction: The standard enthalpy of the reaction is calculated by the formula,
The change in standard Gipp’s free energy of the reaction is calculated as,
To determine: The temperature at which the change in standard Gipp’s energy of the given reaction is zero.
(b)
Answer to Problem 95CWP
The temperature at which the change in standard Gipp’s energy of the given reaction is zero is
Explanation of Solution
Given
The change in standard Gipp’s energy of the given reaction is zero.
Standard enthalpy of the reaction and change in standard entropy of the given reaction is
The change in standard Gipp’s free energy of the reaction is calculated as,
Substitute the value of
Therefore, the temperature at which the change in standard Gipp’s energy of the given reaction is zero is
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Chapter 20 Solutions
Chemistry
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