Understanding the Clausius Clapeyron Relation: Explained Simply

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The Clausius Clapeyron relation, expressed as dP/dT = L/TΔV, describes how pressure must change to facilitate a phase transition for each degree of temperature deviation from the phase change point. It is important to note that the temperature used in the equation is not tied to standard conditions like 1 atm but rather the specific temperature at which the slope is being evaluated on a PT-diagram. Additionally, the relation is a differential expression, indicating that the relationship between pressure and temperature during a phase transition is not linear. Understanding these nuances is crucial for accurately applying the Clausius Clapeyron relation in thermodynamic contexts. This foundational knowledge aids in grasping phase behavior in various physical systems.
Cassiano
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Not sure if this was the right place for this but here goes.
Hello all, so I'm trying to get an intuitive grasp of the Clausius Clapeyron relation dP/dT= L/TdelV. Where L is the latent heat of the phase transition. What I've got so far is this; the relation tells you how much extra pressure must be exerted on a system in order to change its phase for every degree it is away from the temperature it changes phase at 1 atm. Is this correct?

Also the Tempertaure used in the equation would be the temperature of the phase change at standard conditions right? Thank you for the help
 
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Hi Cassiano, welcome to PF!

Cassiano said:
Hello all, so I'm trying to get an intuitive grasp of the Clausius Clapeyron relation dP/dT= L/TdelV. Where L is the latent heat of the phase transition. What I've got so far is this; the relation tells you how much extra pressure must be exerted on a system in order to change its phase for every degree it is away from the temperature it changes phase at 1 atm. Is this correct?

Also the Tempertaure used in the equation would be the temperature of the phase change at standard conditions right?
Not exactly. It is the slope of the boundary between two phases in a PT-diagram. It is not related to any "standard" condition, be it 1 atm or something else. The temperature is simply the temperature at which you are considering the slope. Note also that it is ##dP/dT##, not ##\Delta P / \Delta T##, which is kind of implied by the way you formulated it. In other words, the relationship is not linear between the pressure and the temperature at which the transition takes place.
 
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