Born Haber Cycle

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NaCl (s)
Na (s) ½ Cl2 (g)
Na (g) Cl (g)
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Born-Haber Cycles
eg for sodium chloride
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Born-Haber Cycles
applying Hesss Law
There are two routes from
elements to ionic compound
Apply Hesss Law
?HatmNa ?HatmCl ?H1st IE ?H1st EA
?Hlattice
?Hformation
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Born-Haber Cycles applying Hesss Law
Rearrange to find the lattice energy
?Hlattice
?Hformation - (?HatmNa ?HatmCl ?H1st IE
?H1st EA)
So Born-Haber cycles can be used to calculate a
measure of ionic bond strength based on
experimental data.
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References
Steve Lewis for the Royal Society of Chemistry