Thermodynamics question (ideal gas temperatures)

AI Thread Summary
Doubling the temperature of an ideal gas at constant volume affects its absolute pressure differently depending on the temperature scale used. When using the Kelvin scale, doubling the temperature results in the absolute pressure also doubling, as Kelvin is an absolute scale. In contrast, doubling the Celsius temperature does not lead to a direct doubling of absolute pressure, since the Celsius scale is relative and does not start at absolute zero. The discussion emphasizes the importance of using the Kelvin scale for calculations involving gas laws, as it accurately reflects the relationship between temperature and pressure. Understanding the conversion between Celsius and Kelvin is crucial for solving these thermodynamic problems effectively.
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Homework Statement


The temperature of an ideal gas is doubled while the volume is kept constant...

Does the absolute pressure of the gas double when the temperature that doubles is A) the Kelvin temperature and B) the Celsius temperature. Explain?


The Attempt at a Solution



I can't put the solution to this in words, but I think I might have the right idea... not sure.

1 degree celsius = 274 Kelvin, and if we were to double the celsius temperature we'd have the following:

2 degrees celsius = 275 Kelvin.

So while the celsius temperature doubles the absolute pressure of the gas doubles as well, but if Kelvin were to double then the absolute pressure of the gas wouldn't double but increase exponentially...?
 
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Can anyone throw me a bone here?
 
Difficult not to give the game away here really.
Look at the ideal gas law on wiki, look at the units of what is used.
This shows the temperature scale you should be using.

However: Try to put some numbers into the formula of an isochoric process using both c and K.Hmm acutually this question is confusing me acutally. I don't quite see the point in it as there is really only 1 scale you should be using when dealing with this sort of thing. Someones is going to have to jump in and save my *** now :(
 
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I think you'll get it better if you look at the equations which convert Celsius to kelvin...

It is in fact hard to give you a hint here without giving the whole thing away... but look how the 2 are related... for instance, if you raise 1 degree Fahrenheit that's not equivalent to 1 degree celsius... if you raise 1 degree celsius, how is that related to raising by 1 kelvin?
 
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