Concept explainers
Using data from Appendix 2, calculate the standard enthalpy of the following reaction:
Interpretation:
The standard enthalpy of reaction is to be calculated.
Concept introduction:
The standard enthalpy for a reaction is the amount of enthalpy changethat occursunder standard conditions, that is, at 27°C and
The standard enthalpy of the reaction is to be determined using the equation given below:
Here, the stoichiometric coefficients are represented by m for reactants and n for products, and enthalpy of formation under standard conditions is represented by
The value of enthalpy of formation of an element is zero at its most stable state.
Answer to Problem 1KSP
Solution: Option (e).
Explanation of Solution
Reason for the correct option:
The given reaction is as follows:
From appendix 2,
Calculate the standard enthalpy of the reactionas follows:
Substitute
Hence, the enthalpy change for the reaction is
Hence, option (e) is correct.
Reason for the incorrect options:
Option (a) is incorrect as the calculated value of enthalpy change for the reactiondoes not match with the valuegiven in option (a).
Option (b)is incorrect as the calculated value of enthalpy change for the reactiondoes not match with the value given in option (b).
Option (c) is incorrect as the calculated value of enthalpy change for the reactiondoes not match with the valuegiven in option (c).
Option (d) is incorrect as the calculated value of enthalpy change for the reactiondoes not match with the value given in option (d).
Hence, option (a), (b), (c), and (d) are incorrect.
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