Concept explainers
The isolated O2− ion is unstable so it is not possible to measure the
Interpretation:
Using the Born-Haber cycle for
Concept Introduction:
Born-Haber cycle is based on Hess’s law to calculate the lattice enthalpy of ionic compounds and deals with energy changes in formation of ionic compounds.
The energy released when gaseous state ions of unlike charges that are infinitely farther apart combine to form a stable ionic solid is called Lattice energy. Conversely, the energy required to break the electrostatic force of attraction between the ions of unlike charges in the ionic solid and revert them to gaseous state is also termed as Lattice energy of an ionic solid.
Electron affinity of an atom refers to the energy released when one electron is added to neutral atom in gaseous state.
Hess’s law is applied to calculate the enthalpy changes in a reaction. According to Hess’s law – “The overall enthalpy change of a reaction is equal to the sum of the enthalpy changes involving in each and every individual steps in the reaction.” Thus if a reaction involves ‘n’ steps then enthalpy change
Answer to Problem 9.141QP
Electron affinity of
Explanation of Solution
Given data:
The first step of Born-Haber cycle involves sublimation of solid
The second step of Born-Haber cycle involves dissociation of gaseous
The third step of Born-Haber cycle is ionization of gaseous
The fourth step of Born-Haber cycle is ionization of gaseous
The fifth and final step of Born-Haber cycle is formation of solid
Hence electron affinity of
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Chapter 9 Solutions
Chemistry
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