Gas Thermometer. Not dependent on gas?

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    Gas Thermometer
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The discussion centers on the functionality of gas thermometers and the use of different gases for calibration. Gas thermometers operate based on the ideal gas equation, and while any real gas can be used, it must not behave ideally at all pressures. As pressure decreases, all gases tend to exhibit more ideal behavior, allowing for accurate temperature calculations. Deviations from ideal behavior are accounted for by considering the specific characteristics of the gas used. Thus, gas thermometers can be standardized for calibration with various gases as long as these principles are adhered to.
PFCalvin
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Hello Guys!
I was wondering if anyone can tell me why is it that it doesn't matter what gas we are using in the gas thermometer? Will it still be standardized for calibration if we use different gases?

Thanks.
 
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Yes?
 
The gas thermometer calculates temperature by use of the ideal gas equation but whatever the gas used it must be real and not ideal.A series of pressure readings are taken at gradually reducing pressures and these can be used to extrapolate and find out what the calculated temperature approaches as the pressure appproaches zero.The clever thing is that all gases approach ideal behaviour as the pressure approaches zero.If I remember correctly any other deviations from ideal behaviour are accounted for by taking into account the characteristics of the gas used.
 
Dadface said:
The gas thermometer calculates temperature by use of the ideal gas equation but whatever the gas used it must be real and not ideal.A series of pressure readings are taken at gradually reducing pressures and these can be used to extrapolate and find out what the calculated temperature approaches as the pressure appproaches zero.The clever thing is that all gases approach ideal behaviour as the pressure approaches zero.If I remember correctly any other deviations from ideal behaviour are accounted for by taking into account the characteristics of the gas used.

What do you mean when you say that "... gas used it must be real and not ideal"?
 
PFCalvin said:
What do you mean when you say that "... gas used it must be real and not ideal"?

All gases are real gases and, for example ,do not obey Boyles law exactly.Gases,however, become more ideal in their behaviour as the gas pressure tends to zero and provided that other conditions are met.
 
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