Concept explainers
Calculate the lattice energy of potassium fluoride, KF, using the Born–Haber cycle. Use
Interpretation:
The lattice energy of Potassium fluoride has to be calculated via the Born Haber cycle.
Concept introduction:
Lattice energy:
The amount of energy that is necessary for the conversion of one mole of ionic solid to its constituent ions in gaseous phase is called Lattice energy.
Hess’s law:
The enthalpy change for given set of reactants to the given set of products is the same, whether, the process takes place in single or sequence of steps. This is called as Hess’s law.
Enthalpy is generally calculated from the standard enthalpy of formation.
With the thermodynamic values from Hess’s law, the lattice energy of ionic compound can be determined.
Answer to Problem 9.118QP
The lattice energy of Potassium fluoride is
Explanation of Solution
The above thermo chemical equations can be obtained by applying Hess’s law.
The lattice energy (last row) is obtained by the sum of the enthalpy of sublimation, dissociation, ionization, electron affinity.
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The lattice energy of Potassium fluoride is
The lattice energy of Potassium fluoride is found to be
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Chapter 9 Solutions
Bundle: General Chemistry, Loose-leaf Version, 11th + OWLv2, 4 terms (24 months) Printed Access Card
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