Work and Ideal Gases: Calculate Initial Volume

AI Thread Summary
One mole of an ideal gas performs 1975 J of work during isothermal expansion to a final pressure of 1.2 atm and a volume of 24 L. To find the initial volume, relevant equations include the work done by the gas, W = nRT * ln(Vf/Vi), and the ideal gas law, pV = nRT. The temperature can be derived from the ideal gas law, allowing for the calculation of the initial volume. The discussion emphasizes the need to manipulate logarithmic equations to isolate variables. Understanding these equations is crucial for solving the problem effectively.
Jake4
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Homework Statement



One mole of an ideal gas does 1975 J of work on the surroundings as it expands isothermally to a final pressure of 1.2 atm and a volume of 24 L.

find the initial volume. The universal gas constant is 8.31451 J/K mol




The Attempt at a Solution



Something he touched on in class, but I don't have relevant equations in my notes.

thanks guys!
 
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It seems as if for the work equations, I would also need the Temperature. Is there a way around that? or possibly an equation that allows me to get it?

Also, this is one of those things, that I just simply haven't done before... but how would I solve for a variable within the ln?

you end up with W=nRT*lnVf/Vi So how would I be solving for that Vi?
 
Jake4 said:
It seems as if for the work equations, I would also need the Temperature. Is there a way around that? or possibly an equation that allows me to get it?

Also, this is one of those things, that I just simply haven't done before... but how would I solve for a variable within the ln?

you end up with W=nRT*lnVf/Vi So how would I be solving for that Vi?


Let's take this one step at a time.
That is, let's first set up the equations.
After that we'll see how we can solve them. :smile:


You ask how you can get the temperature T.
Well, perhaps you have overlooked the relevant equation on the wiki page.

It's:

p V = n R T​



Can you set up the equations? :confused:
 
Jake4 said:
It seems as if for the work equations, I would also need the Temperature. Is there a way around that? or possibly an equation that allows me to get it?
T = PV/nR

Also, this is one of those things, that I just simply haven't done before... but how would I solve for a variable within the ln?

you end up with W=nRT*lnVf/Vi So how would I be solving for that Vi?
Use:

e^{\ln x} = xAM
 
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