How much work is done by the system when

2.00 moles of O2 expand from a volume of
3.00 liters to a volume of 5.1 liters against a
constant external pressure of 0.0100 atm?
Answer in units of J.
I get w=-p(deltaV) but what about moles?

4 answers

Do you really care how many moles are there? 1 mol expanding or 100 mols expanding, the only thing that counts is volume difference and p.
The thing is I tried the negative p delta v on my UT homework, and it didn't accept so I thought maybe moles had something to do with it. Unless I was doing the equation wrong.
Did you use -p(Vfinal-Vinitial)
0.0100(5.1-3) = ? L*atm. The problem wants joules, convert by
L*atm x 101.325 = ?J.
Work should be a negative value; make sure to include the - sign when you enter into the database. Keep me posted.
Help it won't accept answer