A liquid mixture containing 55 mol% methanol (1) and 45 mol% water (2) is flowing at 100 kmol/h. The vapor pressures are expressed by lnP = A - ((B)/(T+C)) with P in kPa and T in K.

Component	A	B	C
Methanol	16.4948	3593.39	-35.2249
Water	16.5362	3985.44	-38.9974

a) It is flashed across a valve and into a flash drum held at 350 K. Determine the limiting values of the drum pressure in order to have a two-phase mixture within the flash drum.

b) It is flashed across a valve and into a flash drum held at 90 kPa. Determine the limiting values of the drum temperature in order to have a two-phase mixture within the flash drum.

c) It is flashed across a valve and into a flash drum held at 350 K and 90 kPa. Determine the compositions and flow rates of the overhead and bottoms products.

d) It is flashed across a valve and into a flash drum held at 363 K. If the vapor stream leaving the flash drum has a flow rate of 45 kmol/h, determine the drum pressure as well as the compositions of the liquid and vapor phases

e) It is flashed across a valve and into a flash drum held at pressure of 1 bar. It is required to get a liquid stream with a composition of 25 mol% methanol and 75 mol% water. Determine the temperature and flow rates of the vapor and liquid stream leaving the flash chamber