Concept explainers
Determine the standard enthalpy of formation of ethanol (C2H5OH) from its standard enthalpy of combustion (−1367.4 kJ/mol).
Interpretation:
The standard enthalpy of formation of Ethanol has to be calculated.
Concept Introduction:
The change in enthalpy that is associated with the formation of one mole of a substance from its related elements being in standard state is called standard enthalpy of formation (
The standard enthalpy of reaction is the enthalpy of reaction that takes place under standard conditions.
The equation for determining the standard enthalpies of compound and element can be given by,
To calculate: The standard enthalpy of formation of Ethanol
Answer to Problem 10.130QP
The standard enthalpy of formation of Ethanol is
Explanation of Solution
Standard enthalpy of formation of
Standard enthalpy of formation of Water =
Standard enthalpy of formation of Oxygen =
The equation of formation of Ethanol from its elements can be given as,
The reverse reaction of the above equation gives the combustion of the Ethanol that can be given as,
Water is removed from the reactant side and
Standard enthalpy of formation of Ethanol=
The standard enthalpy of formation of Ethanol was calculated by using the values of standard enthalpies of reactants and the products. The standard enthalpy of formation of Ethanol is found to be
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Chapter 10 Solutions
Chemistry: Atoms First
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