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Homework Help: Heat of Hydration?

  1. Feb 19, 2008 #1
    Heat of Hydration????

    My text asks me to find the (delta H hydration = ??? kj/mol ) and
    the (delta Hsoln =??? kj/mol) when LiI (lithium iodide) is dissolved in water and the solution becomes hotter. Endo/Exo?? And how do I find the kj/mol's. Im a first year student and starting in the middle of the year, so I am a little behind so to speak.
    Sorry about any wrong info. This is my first time on this site.:cry:
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Feb 20, 2008 #2


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    Heat of hydration is the energy given out when the Li and I bond with water - This will be pretty exothermic ( energy given out = negative )
    Heat of solution is the energy needed to break the LiI into separate ions, this takes energy and is endothermic ( energy taken in = positive )

    Be careful though - you could also define the heat of solution to be the total energy generated ie heat hydration + heat solution.
    I don't know how you work these out from first principles, you would eithe rmeasure it in an experiment or use values from tables (of other people experiments )
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