Calculate the work, w, gained or lost by the system when a gas expands from 15 L to 40 L against a constant external pressure of 1.5 atm. 1 L ∙ atm = 101 J

I know its 3.8kJ, but I can't figure out if its suppose to be a negative or not.


And this picture problem...

http://tinypic.com/r/2nreql5/5

And this...

5)

Place the following gases in order of increasing density at STP.

N2 NH3 N2O4 Ar


A)

NH3 < N2 < Ar < N2O4

B )

Ar < N2O4 < N2 < NH3

C)

N2 < Ar < N2O4 < NH3

D)

N2O4 < Ar < N2 < NH3

E)

Ar < N2 < NH3 < N2O4

This post was edited by desertwolf on Nov 17 2013 12:54pm

Is the work being done by the system when an external pressure is being applied? Exothermic or endothermic?

This will let you know whether or not it is positive or negative.

This post was edited by nlin on Nov 17 2013 02:58pm