It asks for the work done ON the gas. The reasons its W = P(Vf-Vi) and not W = -P(Vf-Vi) is because its work ON gas not BY the gas. In U = Q + W, W is work on gas presumably, though I'm not 100% sure.
Homework Statement
Pt. A) A gas is compressed at a constant pressure of 0.632 atm from 7.11 L to 5 L. In the process,
440 J of energy leaves the gas by heat.
What is the work done on the gas?
Answer in units of J
Pt. B)
What is the change in its internal energy?
Answer in units of J...