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Homework Help: Helium gas thermo problem

  1. May 12, 2005 #1
    a 2.00 mol sample of helium gas at 300K and 0.400atm pressure is compressed isothermally to 1.20atm
    Find the volume of the gas, work done on the gas and the energy transfered by heat

    just wondering how to approach this question, and what formulae i hould use where?
  2. jcsd
  3. May 12, 2005 #2

    Chi Meson

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    The formula to use is the one most obvious formula: the ideal gas law formula. It has three variation, called Charles' Law, Boyle' Law and Gaye-Lusac's Law, but I recommend sticking with the ideal gas formula. (Starts with "PV," remember?)

    In an isothermal compression, the temperature stays the same, so there is no change in internal energy, therfore, the work on the gas must equal the heat given off by the gas.

    Since ideal isothermal processes are hyperbolic, the work done must be a "natural log" function of the change in volume. You have probably seen only one natural log function so far, am I right?
  4. May 13, 2005 #3
    thankyou for your help
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