Thermodynamically a gaseous state is more stable than a solid state for a given substance but according to minimum potential energy principle a solid should be more stable than gaseous state? I am unable to mark the difference regarding stability?
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What does "stability" even mean in this context? – probably_someone May 07 '18 at 16:55
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I meant to say the configuration with minimum potential energy – Siddhartha Raja May 07 '18 at 17:00
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We observe that both solids and gasses exist in nature. What does this tell you? – By Symmetry May 07 '18 at 17:08
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related: https://physics.stackexchange.com/q/729698/226902 – Quillo Sep 28 '22 at 16:03
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The gaseous state has a higher entropy than the solid state for a given substance, but we can't say that it's necessary more stable. The most stable equilibrium phase (for a given temperature $T$ and pressure $P$) is the one with the lowest Gibbs free energy $G=H-TS$, where $H$ is the enthalpy (representing the bonding strength, among other factors) and $S$ is the entropy (representing the number of available microstates for our given $T$ and $P$). At sufficiently low temperatures, the solid state is always more stable.
Chemomechanics
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