## Ideal Behavior

Volume: $\Delta S = nR\ln \frac{V_{2}}{V_{1}}$
Temperature: $\Delta S = nC\ln \frac{T_{2}}{T_{1}}$

Lauryn Shinno 2H
Posts: 59
Joined: Fri Sep 28, 2018 12:24 am

### Ideal Behavior

For 9.13 in the 6th edition, it says "During the test of an internal combustion engine, 3.00 L of nitrogen gas at 18.5 degrees C was compressed suddenly and irreversibly to 0.5 L by driving in a piston. In the process, the temperature of the gas increased to 28.1 degrees C. Assume ideal behavior. What is the change in entropy of the gas?" I know I'm supposed to use delta S=nR(ln(v2/v1)), but moles aren't given. Does "assume ideal behavior" mean 1.00 mol?

Kristen Kim 2K
Posts: 70
Joined: Fri Sep 28, 2018 12:16 am

### Re: Ideal Behavior

Yes, the solution says "Assume ideal behavior and 1 mol N2 gas."

chloewinnett1L
Posts: 55
Joined: Fri Sep 28, 2018 12:20 am

### Re: Ideal Behavior

I was going to ask the same thing, should we always take "ideal conditions" to mean 1 mol of gas and pressure=1 atm?

Katelyn Phan 2A
Posts: 61
Joined: Fri Sep 28, 2018 12:23 am

### Re: Ideal Behavior

chloewinnett1L wrote:I was going to ask the same thing, should we always take "ideal conditions" to mean 1 mol of gas and pressure=1 atm?

If not stated otherwise, then such assumption would be sufficient.