Question

Find the work done by the gas during the following stages. (a) A gas is expanded from a volume of 1.000 L to 4.000 L at a constant pressure of 2.000 atm. (b) The gas is then cooled at constant volume until the pressure falls to 1.500 atm

Answer 1

Answer:

a) 607.95 J

b) 0 J

Explanation:

a) Initial volume = 1 L = 0.001 m^3

final volume = 4 L = 0.004 m^3

pressure = 2 atm = 202650 Pa     (1 atm = 101325 Pa)

work done by the gas on the environment = PΔV

P is the pressure = 101325 Pa

ΔV is the change in volume from the initial volume to the final volume

ΔV = 0.004 m^3 - 0.001 m^3 = 0.003 m^3

work done by the gas = 202650 x 0.003 = 607.95 J

b) If the gas is cooled at constant volume, then the gas does no work. For a gas to do work, there must be a change in its volume.

Therefore the work done in cooling at constant volume until pressure falls to 1.5 atm = 0 J