Concept explainers
Calculate
Using (a) Equation 8.4 and (b) Equation 5.19, given that
Interpretation:
The standard enthalpy of the reaction is to be calculated.
Concept Introduction:
The standard enthalpy for a reaction is the value of enthalpy at standard conditions that is under room temperature and pressure.
The standard enthalpy of reaction is to be determined using the equation given below:
Here, the stoichiometric coefficients are represented by m for reactants, and n for products, the enthalpy of formation at standard conditions is represented by
The value of enthalpy of formation of an elementis zero at its most stable state.
The enthalpy of reaction can be calculated as:
Here, BE represents the average value of bond enthalpy.
Answer to Problem 115AP
Solution:
(a)
(b)
Explanation of Solution
a)
The given reaction is as follows:
The enthalpy of reaction can be calculated as:
From table 8.6:
Calculate the standard enthalpy of given reactionas follows:
Substitute,
Hence, the enthalpy of reaction from bond enthalpy value is
b)
The given reaction with its enthalpy of reaction is:
The standard enthalpy of reaction can be calculated as:
From appendix 2,
Oxygen is in its most stable form, so its enthalpy of formation is zero.
Calculate the standard enthalpy of given reaction as follows:
Substitute
Hence, the enthalpy of reaction is
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Chapter 8 Solutions
Chemistry
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