Question

Compute the work done by a gas on the surrounds when it expands against a constant external pressure of 2.00 atm from 5.00 L to 10.00 L at 30C. If 2.00 atm is the gas pressure at 10.00 L, 30C, compute the number of mole of gas. Compute the work that must be done by the surrounds on the gas to return the gas to its initial state using one irreversible compression.

Answer 1

Work/w) = -- Pext. Lor) s em breversible process -- | Against constant pressure) WE - Pext: AV Pext = extemal pressure - Satm AV = Volume change We have expansion of gas from 5L to. TOL. - Se Initial volume VE SL final Volume 1 Vg) = 101 - AV = 19-V DV = (10-5) L 52

Work done - - Pext. AV by gas (w) = - Qatm X 52 --------------- = -10 atm-1 Latm-L = 101.325 I W = -10x101:325 I W = -1013.95 J So, work done by gas on surroundin - Is equal to Vu 1013:95 & Calculation moles pressure (P) = latm Volume (V): 101 Temperaturel Ita 30°C - 30+273 K = 303 K

fyona PV = nRI mole ne pv RT 2x10 0:0821*303 R = 0.0821 atm- mol- n 0.804_mel !_ser moles of gay are 0.804 moles To compress gas gain to intial condition owwyoonding has to work equal to 10 atm-1/ 1013.255)