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Homework Help: Coulomb's Law

  1. May 19, 2007 #1
    I'm having some problems with the calculations associated with this problem:

    Which compound in each of the following pairs of ionic substances has the most exothermic lattice energy?

    (a) LiF
    CsF

    I know I need to use Coulomb's law, but I don't know how to calculate r (the distance between the ion centers)

    Any help is greatly appreciated. Thanks
     
  2. jcsd
  3. May 19, 2007 #2
    nevermind, I have found out that bigger ions have a bigger r value and thus via the inverse proportionality the higher lattice energy corresponds to the lower r value
     
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