Thermodynamics: gas expansion formula or approximation error?

  • Thread starter lucaud
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  • #1
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Homework Statement:
FIRST TYPE: REVERSIBLE PROCESS


SECOND TYPE: REVERSIBLE PROCESS
Relevant Equations:
costant temperature
FIRST TYPE: REVERSIBLE PROCESS At the temperature of 127 ° C, 1 L of CO2 is reversibly compressed from the pressure of 380 mmHg to that of 1 atm. Calculate the heat and labor exchanged assuming the gas is ideal. Q = L = - 34.95 J

CONDUCT 380 mmHg = 0.5 atm L = P1 * V1 * ln (P1 / P2) = 0.5 * 1 * ln (0.5 / 1) = - 0.34 L * atm = -0.34 * 101325/1000 = -35.11 J

SECOND TYPE: REVERSIBLE PROCESS Calculate the maximum work obtainable by making 50 L of oxygen expand isothermally (27 ° C) from 100 atm to 50 atm. Suppose the gas has ideal behavior. 349 * 10 ^ 3 J

PROCESS: L = P1 * V1 * ln (P1 / P2) = 100 * 50 * ln (100/50) = 3465 L * atm = 3465 * 101325/1000 = 351165 J
 

Answers and Replies

  • #2
BvU
Science Advisor
Homework Helper
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Hello @lucaud , welcome !

You need to list the relevant equations you use and mention deviating units if necessary.
In this case the expression for work.

What are the units of pressure in the expression ?
What units did you use in the evaluation ?
 
  • #3
21,153
4,671
It seems to me your results are correct. What is your question?
 

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