Page **1** of **1**

### 4B.13a

Posted: **Thu Feb 06, 2020 9:18 pm**

by **Kristina Rizo 2K**

The question asks to calculate the work for an irreversible expansion against a constant external pressure of 1.00atm to find the final volume of 6.52L. I used the equation w=Pex * delta V and got -2.23L atm, but the answer is 226 and in the SSM it multiplied the -2.23L atm by 101.325. Does anyone know where this number comes from? Is it a constant I am supposed to know?

### Re: 4B.13a

Posted: **Thu Feb 06, 2020 9:31 pm**

by **Michael Nguyen 1E**

This constant is used to convert between L*atm and Joules. It can be found on the provided constants & equations sheet.

### Re: 4B.13a

Posted: **Thu Feb 06, 2020 9:50 pm**

by **205291012**

The constant is important because the final unit of work done must be in Joules not in L*atm.

### Re: 4B.13a

Posted: **Sun Feb 09, 2020 6:33 pm**

by **Matthew Chan 1B**

Hey! The 101.325 J value is just a conversion that we should know. I think it's just good to memorize it as it's definitely important, since we measure work in joules and not L.atm!