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Homework Help: Enthalpy of Dissolution vs. Enthalpy of Solution

  1. Oct 26, 2005 #1
    What is the difference between enthalpy of dissolution and enthalpy of solution?

    I have a lab where I have to measure the change in enthalpy of dissolution of several salts in water. I found the change in enthalpy, however I am supposed to compare them with the real values. I looked in the CRC handbook and there was only a table with changes in enthalpies of solution, these were different values than the ones I got.

    Another thing that I do not undestand is that my reactions were endothermic but my enthalpies of dissolution were all negative. Doesn't enthalpy change indicate if a reaction is exothermic or endothermic? Unless enthalpy of dissolution indicates something else. I used the following equations:

    q = CdT where C is the calorimeter constant

    then

    dH = q / n where dH is the change in enthalpy of dissolution
     
  2. jcsd
  3. Oct 26, 2005 #2
    Negative values indicate a release of energy and exothermicity. Enthalpy of solution and dissolution are the same thing- heat change when one mole of solute dissolves
     
  4. Oct 26, 2005 #3
    Are you serious?
     
  5. Oct 26, 2005 #4
    No I'm lying.
     
  6. Oct 26, 2005 #5

    Physics Monkey

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    You shouldn't lie Cesium, it's probably against some policy here. Hehe.
     
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