# Basic Question Regarding the Combined Gas Law/Equation

## Main Question or Discussion Point

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

Thanks

tiny-tim
Homework Helper
Hello Denyven! They could be in degrees Fahrenheit, provided it was adjusted to º F0, say, where absolute zero is at 0º Fo. Without that adjustment, the equation just won't work. Char. Limit
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.

You could represent it in, say, celcius. Then you would have $$\frac{pV}{T(K)}=\frac{pV}{T(^\circ C)-273.15}$$. You could do it similarily with Fahrenheit if you want, but for simple equations, use the kelvin scale.