(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A 740g quantity of an ideal gas undergoes a reversible isothermal compression at a temperature of 330 K. The compression reduces the volume of the gas from 0.40 m^{3}initially, to 0.32 m^{3}finally. The entropy change of the gas is equal to:

A) -43 J/K B) -150 J/K C) 43 J/K D) 150 J/K E) 0 J/K

2. Relevant equations

ΔS = nR*ln(Vf/Vi)

3. The attempt at a solution

I actually know exactly how to solve this problem. The only thing is, I haven't been able to determine n, the number of moles, without being given the molar mass.

Is there some method to determine n that I'm missing, or has my prof omitted a vital piece of information (the molar mass)?

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# Homework Help: Isothermal Compression and Entropy Change

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