Interpretation:
Whether the standard enthalpy of the reaction is equal to the standard enthalpy of formation or not is to be determined.
Concept introduction:
The standard enthalpy of a reaction is the amount of enthalpy to occur under standard conditions.
The standard enthalpy of a reaction can be determined using the equation given below:
Here, the stoichiometric coefficients are represented by m for the reactants and by n for the products, while the enthalpy of formation under standard conditions is represented by
The value of enthalpy of the formation of an element is zero at its most stable state.
Answer to Problem 93AP
Solution:
(a)
(b)
(c)
(d)
Explanation of Solution
a)
The reaction is given as follows:
Hydrogen in its
For the given equation, the enthalpy of the reaction is as follows:
The enthalpy of formation is zero for
Hence, for the reaction
b)
The reaction is given as follows:
Oxygen in its
For the given equation, the enthalpy of the reaction is as follows:
The enthalpy of formation is zero for
Hence, for the reaction
c)
The reaction is given as follows:
Hydrogen in its
For the given equation, the enthalpy of the reaction is as follows:
The enthalpy of formation is zero for
Hence, for the reaction
d)
The reaction is given as follows:
Oxygen is in its diatomic form, that is,
For the given equation, the enthalpy of the reaction is as follows:
The enthalpy of formation is zero for
Hence, for the reaction
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Chapter 5 Solutions
Looseleaf Study Guide For Chemistry
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