On an exam I got this question:(adsbygoogle = window.adsbygoogle || []).push({});

[PLAIN]http://img849.imageshack.us/img849/5732/spontaneity.png [Broken]

but at the time I had no idea how to answer it. I still don't really know if I can answer it. I can explain it mathematically with the equation:ΔG = ΔH - TΔSseeing as a spontaneous reaction requires a negative change in G and therefore if the sign of ΔH and ΔS are different then temperature will be a determining factor as to whether or not ΔG will be negative. I have no idea what I would need to plot on a graph though. As for examples of reactions of each type I suppose I needed to have a few example reactions memorised.

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# Explaining why some reactions are spontaneous at certain temperatures

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