- #1

- 3

- 0

## Homework Statement

A monatomic ideal gas is compressed adiabatically. What is ΔS of the gas?

n = 1.00

vi = 10.00 L

vf = 4.00 L

Constant External Pressure = 50.00 atm

## Homework Equations

ΔU = q + w = 0 + (-PextΔV)

ΔS = ∫[(qrev)/T]dQ

## The Attempt at a Solution

In order to calculate ΔS you have connect two thermodynamic states with a reversible path. I assumed that the ΔS of the system is 0 because dQ is 0 for adiabatic processes). Then second state focuses on ΔS of the surroundings that has an external pressure associated with it.

I found Tf = 322.06 K by using the ΔU equation

I am not sure what to do at this point, because every single attempt I made has led me to a negative ΔS.