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HethensEnd25

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## Homework Statement

A well-insulated tank of volume 6 m

^{3}is divided into two equal volumes. The left part is initially filled with air at 100 C and 2 bar, and right side cell is initially empty. A valve connecting two cells will be opened so that gas will slowly pass from cell 1 to cell 2. The wall connecting the two cells conducts heat sufficiently well that the temperature of gas in both cells will always be the same. Plot on the same graph a) the pressure in the second tank versus the pressure in the first tank, and b) the change in the total entropy of the system versus pressure in the tank 1. Do these calculations with the increments of 5% of the gas transferred until all gas is transferred to tank 2. At these temperatures and pressures air can be considered as an ideal gas with constant heat capacity. Before plotting the total entropy change what do you think final pressure will be? Also will the temperature change? Since entropy increases for any natural process, what do you think entropy will be at the equilibrium pressure (minimum or maximum)?

## Homework Equations

PV=nRT

entropy Balance

## The Attempt at a Solution

I know that for a valve it is isenthalpic so the enthalpy that that goes from partition1 into partition2 will be the same. I also know that the second pressure or the maximum amount of pressure that would be released into partition2 would be 1 bar as it would have to find equilibrium with that of the pressure coming from partition1 at some point. I know the final temperature would be the same again because it is isenthalpic and "well insulated".

I just am confused on how they want me to approach this problem. It says to do the increments in 5% of the gas transferred. Are they referring to the mols ? And what about the entropy wouldn't it continuously increase seeing that this partition is being filled?here is my attached attempt at a solution.

Best Regards,

D

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