Concept explainers
Interpretation:
The standard enthalpy of formation of benzene and acetylene, and hence, the enthalpy change for the formation of benzene from acetylene are to be calculated.
Concept introduction:
The standard enthalpy for a reaction is the amount of enthalpy that occursunderstandard conditions
The standard enthalpy of a reaction is determined by using the equation given below:
Here, the
The value of the enthalpy of formation of an element is zero at its most stable state.
Answer to Problem 102AP
Solution:
Explanation of Solution
Given information:
The given reaction is as follows:
The reaction for the combustion of acetylene isas follows:
The reaction for the combustion of benzene isas follows:
From appendix 2,
The oxygen gas is in its most stable form, so its enthalpy of formation is zero.
Calculate the standard enthalpy for the combustion of acetylene as follows:
Substitute
Rearrange the above equation for
Calculate the standard enthalpy for thecombustion of benzene as follows:
Substitute
Rearrange the above equation for
Calculate the enthalpy of the reaction for the formation of benzene from acetylene as follows:
Substitute
Theenthalpy change for theformation of benzene from acetylene is
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Chapter 5 Solutions
Chemistry
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