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Comparing thermo dynamic processes

  1. Feb 18, 2013 #1
    1. The problem statement, all variables and given/known data

    in a cylinder, 1.2 mol of an ideal gas, gamma = 1.67 initially at 3.60 x10^5 pa
    and 300k, is compressed until the volume is halved.

    I need help with 1) c

    Compute work done on the gas if the compression is:


    a) isothermal
    b) adiabatic
    c) isobaric

    2) in which case is the absolue value of the change in internal energy of the gas the greatest? least?

    2. Relevant equations

    I think i have a and b worked out.

    3. The attempt at a solution

    for c) would this be the correct approach?

    is this part correct?

    V1 = ?
    V2 = 1/2V1

    w = p(V2 - V1)
    w = p(1/2v - v)

    pv = nrt

    w = -1/2nrt?

    2) greatest is isobaric because?
    least is isothermal because delta u =0 constant temp and temp is related to change in internal energy.
  2. jcsd
  3. Feb 18, 2013 #2


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    How can the gas get compressed if the process is isobaric? What other property must change?
  4. Feb 18, 2013 #3
    the volume is being compressed. But, th pressure remains constant so the area of work is less than the other 2 processes? Adiabatic is the most?
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