Adiabatical Compression Question

  • Thread starter Reptic
  • Start date
  • Tags Tags
    Compression
4 replies · 1K views · last reply
Reptic
Messages
10
Reaction score
0

Homework Statement


Air at 20C is compressed adiabetically from 1 bar to 10 bar. What will its temperature be?

Homework Equations


pV = nRT,
P1P2=T1T2
P1Vλ1=P2V2λ

The Attempt at a Solution

Handwritten working on lined paper solving an adiabatic compression problem: P1 = 1, P2 = 10, T1 = 20, V1 = RT1/P1 = 8.31 x 20 / 1 = 166.2, then V1 over 10^(1/γ) equals V2 = 32.038, and T2 = P2V2/R = 10 x 32.038 / 8.31 = 38.6 C.

In picture...[/B]
 
Is PV = nRT valid for the Celsius temperature scale?
 
Yes, you need to use an absolute temperature scale such as Kelvin.
 
Reptic said:
no, should be kelvin 293 right?
Are you familiar with the first law of thermodynamics? Are you supposed to assume that the compression takes place reversibly?

Chet