A system consists of two glass bulbs with identical 20 liter
A system consists of two glass bulbs with identical 20 liter volumes, in equilibrium with the surroundings at a temperature T = 400 K. The bulbs are connected to one another by narrow tube, and the tube is closed with a stopcock. Initially, the bulb on the left is lled with 1 mole of helium gas, and the bulb on the right is lled with 1 mole of neon gas. When the stopcock is opened, the two gases mix. Assume ideal gas behavior. What are S; Ssurr ; and Suniv? Express your answers in Joules/K. What is A in Joules? What is the maximum work that could be extracted from this mixing process if one were so inclined? How might one extract it?
Solution
Change in entropy of helium gas, S1= N1Rln(0.5) = 1 mol*8.314 J/molK*(-0.693) = -5.76 J/K
Change in entropy of helium gas, S2= N2Rln(0.5) = 1 mol*8.314 J/molK*(-0.693) = -5.76 J/K
total change in entropy of the system= S1+S2 = -5.76-5.76 = -11.52 J/K
