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Concept explainers
For the reaction
(a) Predict the enthalpy of reaction from the average bond enthalpies in Table 8.6. (b) Calculate the enthalpy of reaction from the standard enthalpies of formation (see Appendix 2) of the reactant and product molecules, and compare the result with your answer for part (a).
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Interpretation:
The
Concept Introduction:
The enthalpy of the reaction by using the bond enthalpy is calculated by the expression, which is as:
Here,
The enthalpy of the reaction by using the standard enthalpy of formation is calculated by the expression, which is as:
Here,
Rules to write the Lewis structure are as:
The skeletal structure of the compound is drawn in which the less electronegative element is placed as the central atom, which is surrounded by substituent atoms.
The total number of valence electrons for the compound is determined.
Subtract two electrons for each bond in the skeletal structure from the total number of valence electrons to know the number of remaining electrons.
Complete the octet of each terminal atom by placing a pair of electrons from the remaining electrons.
If any of the electrons are remaining after completing the octet of terminal atoms, place the remaining electrons as a pair on the central atom.
Answer to Problem 83QP
Solution:
The
The
Explanation of Solution
a)The enthalpy of reaction from the average bond enthalpies.
The given reaction is
The bond enthalpy value of
The bond enthalpy value of
The bond enthalpy value of
The bond enthalpy value of
The bond enthalpy value of
The Lewis structure of the given reaction is drawn in order to determine which bond is formed and which is broken.
In the given reaction,
The
Substitute the value
b) The enthalpy of reaction from the standard enthalpies of formation
The given reaction is
The value of
The value of
The value of
The value of
Here,
The value of change in the enthalpy for atoms in their standard state is zero. In the reaction,
Substitute
The values of
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Chapter 8 Solutions
Chemistry
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