# Thermodynamics Question Calculating change in temperature

• Gaith

## Homework Statement

[/B]
50 moles of an ideal gas for which Cp= 5/2R and Cv=3/2R initially has a pressure of 1x10^5 Pa, and a volume of 1.0m^3. It undergoes a process where the pressure and volume both double while they stay proporitional to each other: P=constV. What is the change in temperature for this process?

ΔU= Q-W
PV=nRΔT
ΔU= nCv(ΔT) [/B]

## The Attempt at a Solution

So I started by trying to use PV=nRΔT and calculating T, however I wasnt successful. The answer in my book is in Kelvins, so I tried converting the temperature that I calculated to Kelvins, however it was still wrong.

I'm thinking that I might need to take the integral: ∫ PVdv but I am not sure if that's correct either.

Can somone please help me out, It would be greatly appreciated.

The correct answer is: 720K

Last edited:
Hello.
PV=NRΔT

The above equation is not correct. The ideal gas law is PV = nRT, not PV = nRΔT.

From PV = nRT can you calculate the initial temperature? How about the final temperature?

From the ideal gas law, what is the initial temperature? From the ideal gas law, what is the final temperature?

Chet