chemistry please help...?

Question

A gas is contained in a cylinder with a sliding piston. Weights are placed on top of the piston that produce a pressure of 70588 Pascals. Heat is removed as a quantity of energy equal to 3000 J The volume of the gas is reduced from 185.0 L to 84.4 L.


Calculate DE for the process in Joules.


expansion work = −PextΔV Pext = external pressure

Answer 1

Pext = external pressure = 70588 Pascals
ΔV = change in volume = 84.4 L - 185.0 L = - 100.6 L

to use in the equation, the volume must be in cubic meters:
100.6 L / 1000 L/cubic meters = 0.1006 cubic meters

The expansion work (in Joules) = - 70588 Pascals X - 0.1006 cubic meters
= 7101.15 Joules