Variation of vapor pressure with temperature

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Discussion Overview

The discussion revolves around the variation of vapor pressure with temperature, specifically focusing on how to plot data to achieve a linear representation. Participants explore the mathematical relationships involved and the appropriate plotting methods.

Discussion Character

  • Homework-related, Mathematical reasoning

Main Points Raised

  • One participant expresses uncertainty about the mathematical relationship needed to plot vapor pressure data and initially suggests that plotting lnP vs T would yield a straight line, but later acknowledges that the correct approach is lnP vs 1/T.
  • Another participant introduces the Clausius-Clapeyron equation as relevant to the discussion.
  • A third participant references the one component, two phase version of the Clausius-Clapeyron equation, indicating a specific context for its application.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the plotting method, as there is a clear expression of uncertainty and differing initial hypotheses regarding the relationship between vapor pressure and temperature.

Contextual Notes

The discussion highlights a potential misunderstanding of the mathematical relationships involved in vapor pressure plotting, with some assumptions about the nature of the data and its representation remaining unexamined.

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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