Variation of vapor pressure with temperature

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SUMMARY

The variation of vapor pressure with temperature can be accurately represented using the Clausius-Clapeyron equation. To obtain a straight line from the data, one must plot lnP (natural logarithm of vapor pressure) against 1/T (inverse of temperature). This method reveals the exponential relationship between vapor pressure and temperature, confirming that the initial assumption of plotting lnP vs T was incorrect.

PREREQUISITES
  • Understanding of the Clausius-Clapeyron equation
  • Knowledge of vapor pressure concepts
  • Familiarity with logarithmic functions
  • Basic principles of thermodynamics
NEXT STEPS
  • Study the Clausius-Clapeyron equation in detail
  • Learn how to derive vapor pressure from temperature data
  • Explore the implications of plotting lnP vs 1/T
  • Investigate other thermodynamic equations related to phase changes
USEFUL FOR

Chemistry students, researchers in thermodynamics, and anyone studying phase transitions in liquids and gases will benefit from this discussion.

utkarshakash
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Homework Statement


The following link shows the variation of vapor pressure with temperature. In which way the data should be plotted to obtain a straight line?

http://www.chem.purdue.edu/gchelp/liquids/vpress.html


The Attempt at a Solution



For this, I need to know exactly the mathematical relationship which I can't seem to find anywhere. Anyways, my immediate guess would be that the graph is an exponential function. So plotting the graph of lnP vs T would give me a straight line but the correct answer is lnP vs 1/T. I'm sure I'm missing something here.
 
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Are you familiar with the Clausius Clapeyron equation?

Chet
 
This is the one component, two phase (solid-gas, liquid-gas) "version" of the Clausius-Clayperon equation.
 
Thanks to both of you.
 

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