What is the Work Done by an Ideal Gas Expanding at Constant Temperature?

AI Thread Summary
The discussion focuses on calculating the work done by an ideal gas expanding at constant temperature, specifically using the equation W=2.303nRTlog(v2/v1). A participant calculated the work to be 4613.959 J but questioned the answer of 554.6 J, suspecting a misunderstanding of logarithmic functions. The correct formula for work in this context is clarified as W=nRTln(V2/V1), where ln represents the natural logarithm. The calculations involve two moles of gas, a temperature of 400 K, and the gas expanding to double its initial volume. The confusion between logarithmic bases is highlighted as a key point in resolving the discrepancy in the results.
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Homework Statement



Two moles of an ideal gas expand to double the initial volume at a constant temperature of 400 K. Calculate the work done by the process.

Homework Equations



W=2.303nRTlog(v2/v1)

The Attempt at a Solution



i tried the formula and got 4613.959 J but the answer is 554.6 J
 
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Are you sure it isn't log(V2/V1)? I'm used to the form W=nRTln(V2/V1). I can't get either of those answers. Can you show how you got that?
 
hage567 said:
Are you sure it isn't log(V2/V1)? I'm used to the form W=nRTln(V2/V1). I can't get either of those answers. Can you show how you got that?

n=2; v2=2*v1;T=400 K; R=8.32

W=2.303nRTlog(v2/v1)
= 2.303*2*8.32*400*log(2v1/v1)
= 2.303*2*8.32*400*log(2)
= 2.303*2*8.32*400*0.3010
= 4613.959

we generally use logarithms and i don't know wat is "ln"
 
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