Constant-volume gas thermometer

[Rblswimmer456]

Homework Statement

The pressure in a constant-volume gas ther-
mometer is 0.811 atm at 100◦C and 0.5 atm
at 0◦C.

A) What is the temperature when the pressure
is 0.656922 atm?
Answer in units of ◦C.

B) What is the pressure at 138◦C?
Answer in units of atm.

Homework Equations

well I know that P1/T1=P2/T2 but I don't know how to go about it since two pressure and temperatures are given so I don't know the formula to find the third.

for part B I figured I would have to get part A before attempting the second part.

The Attempt at a Solution

 

[rock.freak667]

They gave you the pressures at two temperatures. You can use either one as P1 and T1.

I mean P1 and the corresponding T1 that is.

 

[Dadface]

I think the main problem is that the gas differs from ideal behaviour and by a substantial amount.Using the given data P/T is nowhere near constant.

 

[rock.freak667]

Then it is likely that some sort of linear relationship should be found using the two points.