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Working out Bond Enthalpy from a Born Haber cycle?

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    How would you find the value of a F-F bond from this data? I've drawn a correct cycle out but the calculation doesn't make sense to me. My teacher missed this part out of our lessons so any help would be appreciated :-) It is in context of AgF.

    Enthalpy change Value / kJ mol–1
    Enthalpy of atomisation for silver +289
    First ionisation energy for silver +732
    Electron affinity for fluorine –348
    Experimental enthalpy of lattice dissociation for silver fluoride +955
    Enthalpy of formation for silver fluoride –203

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    E(F–F) + 732 + 289 + +203 = 348 + 955
    E(F–F) = 79
    2E(F–F) = 158 KJ/mol
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    (Original post by typicalvirgo)
    How would you find the value of a F-F bond from this data? I've drawn a correct cycle out but the calculation doesn't make sense to me. My teacher missed this part out of our lessons so any help would be appreciated :-) It is in context of AgF.

    Enthalpy change Value / kJ mol–1
    Enthalpy of atomisation for silver +289
    First ionisation energy for silver +732
    Electron affinity for fluorine –348
    Experimental enthalpy of lattice dissociation for silver fluoride +955
    Enthalpy of formation for silver fluoride –203

    ANSWER:
    Spoiler:
    Show
    E(F–F) + 732 + 289 + +203 = 348 + 955
    E(F–F) = 79
    2E(F–F) = 158 KJ/mol
    The silver fluoride Born Haber cycle is fundamentally the same as the sodium chloride cycle, to which I am linking you ...

    Open this page and click on "The Born Haber cycle NaCl"
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    (Original post by charco)
    The silver fluoride Born Haber cycle is fundamentally the same as the sodium chloride cycle, to which I am linking you ...

    Open this page and click on "The Born Haber cycle NaCl"
    Thank you!!!!!
 
 
 
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