Why Do Substances Undergo Radical Changes During Phase Transitions?

Thread starter loom91
Start date Oct 11, 2006
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Phase Phase transition Transition

AI Thread Summary

Phase transitions, like fusion and evaporation, occur when substances undergo significant changes in their physical state, often linked to temperature and pressure variations. These transitions are characterized by abrupt changes in properties such as Gibbs energy and heat capacity, indicating a shift in the system's thermodynamic state. The mechanisms behind these radical changes involve molecular interactions and energy distribution, leading to a reorganization of the substance's structure. Understanding these processes requires exploring the underlying physics and chemistry that govern molecular behavior during transitions. Overall, phase transitions represent critical points where a substance's characteristics fundamentally alter.

Oct 11, 2006

loom91

Hi,

I was wondering, what actually are phase transitions such as fusion or evaporation? I know thermodynamic definitions such as points where the Gibbs energy is non-analytic or heat capacity changes abruptly, but these say nothing about mechanism. Why does a substance suddenly change its characteristics radically? Thanks.

Molu

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Oct 25, 2011

oghenez

http://en.wikipedia.org/wiki/Phase_transition

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