Concept explainers
Interpretation:
The
Concept Introduction:
Hess’s Law: The total enthalpy change for a
Answer to Problem 102QRT
For Given Step 1, the value is
For Given Step 2, the value is
For Given Step 3, the value is
The standard reaction enthalpy value for net equation is
The overall reaction is endothermic.
Explanation of Solution
Given Step 1:
Using the above given reaction enthalpy is calculated by subtracting the summation of formation of products from the summation of formation enthalpy of reactants.
Given Step 2:
Using the above given reaction enthalpy is calculated by subtracting the summation of formation of products from the summation of formation enthalpy of reactants.
Given Step 3:
Using the above given reaction enthalpy is calculated by subtracting the summation of formation of products from the summation of formation enthalpy of reactants.
The above three expressions are added in order to obtain the net equation as follows,
Summation of the given equations and eliminating the reactants that show as products during summation are done. Then, the remaining reactant and products which form the net equation for the reaction and their individual reaction enthalpy changes values are added to get the net reaction enthalpy change value.
The obtained net equation value is positive hence, the reaction is endothermic.
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Chapter 4 Solutions
Chemistry: The Molecular Science
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