The apparatus in Exercise 5.20 is again evacuated. Then 35.0 g of chloroform, CHCl₃, is placed in flask A and 35.0 g of acetone, CH₃COCH₃, is placed in flask B. The system is allowed to come to equilibrium at 25°C with stopcock C closed. The vapor pressures of chloroform and acetone at 25°C are 195 Torr and 222 Torr, respectively.

(a) What is the pressure in each flask at equilibrium?

(b) The stopcock is now opened. What will be the final composition of the gas and liquid phases in each flask once the system reaches equilibrium, assuming ideal behavior?

(c) Acetone and chloroform solutions show negative deviations from Raoult’s law. How will this behavior affect the answers given in part (b)?

Exercise 5.20

Consider an apparatus in which A and B are two 1.00-L flasks joined by a stopcock C. The volume of the stopcock is negligible. Initially, A and B are evacuated, the stopcock C is closed, and 1.50 g of diethyl ether, C₂H₅OC₂H₅, is introduced into flask A. The vapor pressure of diethyl ether is 57 Torr at –45°C, 185 Torr at 0°C, 534 Torr at 25°C, and negligible below –86°C.