Understanding the Role of Calibration in Vapour Pressure Determination

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The discussion centers on the use of Knudsen Effusion to determine the vapor pressure of a compound, specifically using naphthalene for calibration. The equation ln P = A - B/T is employed, where P represents pressure, T is temperature, and A and B are constants derived from literature. The purpose of utilizing the literature equation alongside lab-calculated values is to establish a reliable calibration curve for the instrument measuring vapor pressure of other compounds. Known parameters, such as the vapor pressure of naphthalene, serve as a reference point, while the calibration process aims to define the unknown parameters related to the device's performance. This dual approach enhances accuracy and reliability in measuring vapor pressures of different substances. Understanding the relationship between known and unknown parameters is crucial for effective calibration and application of the method to other compounds.
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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?
 
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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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