please answer three, else I won't rate

1. A fractionation column is fed with a 100 kmol/h of a solution containing 75 mol% methanol and 25 mol % ethanol. The feed is saturated liquid at the column operating pressure of 101.3kPa. The relative volatility of the system may be assumed to be constant at 1.56. The distillate contains 96 mol %methanol and bottoms product is 95 mol% ethanol, It is desired to withdraw a side stream containing 80 mol% ethanol at a rate of 15 kmol/h from the stripping section. If the reflux ratio employed is 20% in excess of the minimum and the condenser used is total, determine ethanol is number of theoretical plates required. 2. One hundred kmol of an equimolar mixture of A and B with a relative volatility of 2.3 is to be separated into a distillate product with 98.5 mol% A, a bottoms product with 2 mol% A, and an intermediate liquid product containing 80 mol% A with 40% of A in the feed recovered. The feed enters the column at its bubble point. Determine: (a) Amounts of each product (b) Minimum reflux ratio (c) How much greater is the minimum reflux rate because of the withdrawal of side stream? (d) If the reflux ratio employed is 3, find the number of theoretical plates. 3. Two liquid streams made up of benzene and toluene, one containing 40 mol% benzene and the other containing 70 mol% benzene are available in equal amounts at their bubble points as feed streams to a distillation column. It is desired to produce a distillate containing 98 mol% benzene and residue containing 97 mol% toluene. Reflux ratio employed is 2.5 mol/mol distillate. Determine: (a) The number of theoretical plates if the streams are combined and admitted to the column as saturated liquid at a single point (b) The number of plates if the feeds enter as saturated liquids at two different plates. Equilibrium data (mole fraction benzene) are: 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 0.95 1 0 0.205 0.369 0.502 0.618 0.706 0.789 0.849 0.907 0.955 0.978 1