Physics: Expansion at constant pressure

AI Thread Summary
The discussion focuses on calculating the number of moles, final temperature, and work done by an ideal monoatomic gas expanding at constant pressure. The user is struggling with the calculation using the ideal gas law (PV=nRT) and is converting units incorrectly, specifically converting volume from cubic meters to liters. The method of using the equation of state for the initial state is deemed appropriate, but the conversion of units is highlighted as a potential error. There is a suggestion to keep the volume in cubic meters rather than converting it. Accurate calculations are essential for determining the correct values for moles and other properties of the gas.
FutureE'neer
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An unknown number of moles of an ideal monoatomic gas expand reversibly from Vi = 2.30 m3 to Vf = 3.10 m3, at a constant pressure of 1.71 atm and an initial temperature of 300 K.
Find the number of moles of gas.
Find the final temperature of the gas K.
Calculate the work done by the gas.

I cannot find the number of moles and I don't know what I'm doing wrong.
I'm using PV=nRT
Converting the pressure in atm to N/m^2 and m^3 to L. I'm using the initial volume for V, 8.315 for R and the initial temp in K and solving for n. I keep getting the same answer and it is coming up wrong. Please help!
 
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Keywords are "ideal monoatomic gas expand reversibly "
What does that mean to you?
 
that's how much it fluctuate's?
 
FutureE'neer said:
I cannot find the number of moles and I don't know what I'm doing wrong.
I'm using PV=nRT
Converting the pressure in atm to N/m^2 and m^3 to L. I'm using the initial volume for V, 8.315 for R and the initial temp in K and solving for n. I keep getting the same answer and it is coming up wrong. Please help!
Can you show what you did (and how do you know is wrong)?
The method (using equation of state for initial state) seems OK.
 
Don't change m^3 to litres
 

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