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Comparison Calibration Method

  1. Feb 10, 2016 #1
    I am doing a lab which involves the determination of vapour pressure of a particular compound by Knudsen Effusion. Like other analytical methods it involves calibration but we are using the know vapour pressure of naphthalene because its in the accepted range. So we have an equation for the vapor pressure of naphthalene from literature and we are also performing a calibration in the lab. What I am not understanding is how to use the calibration curve in the form

    ln P= A-B/T

    (where P is the pressure, T is the temperature and A and B are constants) for naphthalene to calibrate the instrument for another compound. What is the purpose of using the equation from literature and then calculating it in lab ourselves?
  2. jcsd
  3. Feb 11, 2016 #2


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    Staff: Mentor

    Please elaborate on the details, I have problems understanding what you are doing.

    First things first: typically there known parameters (in this case: describing the naphthalene) and unknown parameters (in this case: describing the calibrated device). Can you classify what you have into these groups?
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