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Two more for the champs

  1. Apr 28, 2005 #1
    Well, I've been impressed - to say the least - with how quickly my questions have been answered. So, here are two more:

    N2O4 --> 2NO2

    Under standard conditions: Delta G is 2.8 kJ. What temp will make it spontaneous?


    What amount of Cd(OH)2 will dissolved in 1.00 x 10^2 L of aq. solution?

    Any takers? Thanks in advance
  2. jcsd
  3. Apr 28, 2005 #2


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    You'll simply need to find an appropriate equation for this one. Suggest one to us.

    This is also a basic problem. What's the Ksp? What can you do from there?
  4. Apr 28, 2005 #3

    You should have a table of standard state enthalpy and entropy data somewhere in your book, probably the back. Thus calculate delta H and delta S for the reaction. In order to find a temperature to make the reaction spontaneous you want H-TS<0 or H<TS or T<H/S (be careful of the sign here, you may have to flip it if S is negative).
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