Work and Ideal Gases: Calculate Initial Volume

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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:

[tex]e^{\ln x} = x[/tex]AM