Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Basic Question Regarding the Combined Gas Law/Equation

  1. Mar 10, 2010 #1
    Hello All,
    I was wondering, in the combined gass law [tex]\frac{p_{1}V_{1}}{T_{1}}=\frac{p_{2}V_{2}}{T_{2}}[/tex] Does [tex]T_{1}[/tex] and [tex]T_{2}[/tex] have to be in kelvins, or can they be any other unit of temperature as long as a consistency of units is used?

    Thanks
     
  2. jcsd
  3. Mar 10, 2010 #2

    tiny-tim

    User Avatar
    Science Advisor
    Homework Helper

    Hello Denyven! :smile:

    They could be in degrees Fahrenheit, provided it was adjusted to º F0, say, where absolute zero is at 0º Fo. :wink:

    Without that adjustment, the equation just won't work. :redface:
     
  4. Mar 10, 2010 #3

    Char. Limit

    User Avatar
    Gold Member

    Just to let you know, as Kelvin is the Celsius scale with the origin at zero, so Rankine is the Fahrenheit scale with the origin at zero.

    However, the scale must be set up so that the absolute coldest temperature is zero.
     
  5. Mar 11, 2010 #4
    You could represent it in, say, celcius. Then you would have [tex]\frac{pV}{T(K)}=\frac{pV}{T(^\circ C)-273.15}[/tex]. You could do it similarily with Fahrenheit if you want, but for simple equations, use the kelvin scale.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook