A liquid mixture containing 0.45 mol fraction of heptane and 0.55 mole fraction ethyl benzene is fed as saturated vapor to a distillation column at a flow rate of 200 kgmol/h for product separation. The distillation operates at 1 atm (absolute). The recovery of heptane (to the distillate product) is 95% and the required heptane purity in the distillate is 0.98 (mole fraction). Calculate the following: a. The distillate and bottom flowrates
b. The minimum reflux ratio
c. The minimum number of stages
d. The number of stages at a reflux ratio of 1.5Rmin

Amass of m 1.5 kg of steam is contained in a closed rigid container. initially the pressure and temperature of the steam are: p 1.5 mpa and t 240°c (superheated state), respectively. then the temperature drops to t2= 100°c as the result of heat transfer to the surroundings. determine: a) quality of the steam at the end of the process, b) heat transfer with the surroundings. for: p1.5 mpa and t 240°c: enthalpy of superheated vapour is 2900 kj/kg, specific volume of superheated vapour is 0. 1483 m/kg, while for t 100°c: enthalpy of saturated liquid water is 419kj/kg, specific volume of saturated liquid water is 0.001043m/kg, enthalpy of saturated vapour is 2676 kj/kg, specific volume of saturated vapour is 1.672 m/kg and pressure is 0.1 mpa.

Which of the following is an easy way to remember the modified “x” tire rotation? a. nondrive wheels straight, cross the drive wheels b. drive wheels straight, cross the nondrive wheels c. drive wheels crossed, nondrive wheels straight d. drive wheels crossed, nondrive wheels crossed

Coiled springs ought to be very strong and stiff. si3n4 is a strong, stiff material. would you select this material for a spring? explain.