So, can you find the temperature at which this reaction will be spontaneous?

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The discussion centers around two chemistry questions regarding thermodynamics and solubility. The first question involves determining the temperature at which the reaction N2O4 to 2NO2 becomes spontaneous, given a standard Gibbs free energy change (Delta G) of 2.8 kJ. The key to solving this is using the equation G = H - TS, where one needs to calculate Delta H and Delta S from standard state data to find the temperature threshold for spontaneity, specifically T = H/S, while considering the sign of S.The second question addresses the solubility of Cd(OH)2 in a 100 L aqueous solution. To solve this, one must identify the solubility product constant (Ksp) for Cd(OH)2 and apply it to determine how much of the compound will dissolve in the given volume. This involves basic principles of solubility equilibria and Ksp calculations.
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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?

And

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

Any takers? Thanks in advance
 
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Under standard conditions: Delta G is 2.8 kJ. What temp will make it spontaneous?

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

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

This is also a basic problem. What's the Ksp? What can you do from there?
 
G=H-TS

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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