How Does Isothermal Expansion Affect Work Done and Temperature in an Ideal Gas?

[fishingaddictr]

Suppose 145 moles of a monatomic ideal gas undergo an isothermal expansion from 1.00m^3 to 4.00m^3, as shown in figure. what is the temp at the beginning and end of this process? how much work is done by the gas during the expansion?

http://www.physics.brocku.ca/Courses/1p23/images/FG18_24.JPG

since it is isothermal the temperature is constant correct?
so to solve for the temperature would i just use pv=nrt with the respective values for pressure and volume?
and for the work done W=nrtln(vf/vi)

thanks

 

[KoGs]

You have p_i and p_f, and also v_i and v_f. Can you think of a formula that uses p and v ?

Hint: What are the units for pressure?

 

[fishingaddictr]

so i wouldn't use pv=nrt?

 

[KoGs]

Try it out. Plug in the values of p_i and v_i into that formula.
Then plug in the values of p_f and v_f into that formula.
See what you get.

 

[fishingaddictr]

im getting .332 for the temperature.

 

[fishingaddictr]

and for the work i get 1670.42j

 

[KoGs]

Now you tell me. Is temperature constant?

 

[fishingaddictr]

yup yup. thought it was tryin to trick me by askin the temp of beginnin and end like it was going to be two different values.