## thermodynamically stable vs unstable compound

$\Delta G^{\circ}= \Delta H^{\circ} - T \Delta S^{\circ}$

$\Delta G^{\circ}= -RT\ln K$

$\Delta G^{\circ}= \sum \Delta G_{f}^{\circ}(products) - \sum \Delta G_{f}^{\circ}(reactants)$

Peter Dis1G
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Joined: Fri Sep 29, 2017 7:04 am

### thermodynamically stable vs unstable compound

Do we have to be able to distinguish and identify those kinds of compounds?

Austin Ho 1E
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Joined: Fri Sep 29, 2017 7:04 am
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### Re: thermodynamically stable vs unstable compound

You should be able to distinguish whether a compound is thermodynamically stable (or unstable) by looking at its ΔG° of formation: if ΔG is positive, then its formation is not spontaneous; likewise, the reverse reaction is spontaneous, and it will decompose into its reactants.

For a thermodynamically stable compound, it should be stable if its ΔG° of formation is negative.