Q. A set of standard stainless steel pipes, each of internal diameter 26.65 mm and 6000 mm length, is used to make a plug flow reactor by joining them in series to carry out degradation of polyethylene. Seven such pipes are required to obtain a conversion of 66% at 450 K. The minimum number of […]
Q. In a closed piston-cylinder system, methane was observed to obey the following equation of state P(V– nb) = nRT where b = 0.029 m3/mol. The temperature and volume are 500 ºC and 5 m3 respectively for 100 moles of methane. At this state of the system, the isobaric rate of change of temperature with
Q. The volume of liquid filled in a spherical storage tank of radius R is computed from height of liquid, h, in the outside tube (neglecting the volume of liquid in the outside tube) as Ans: 1.80 to 2.00
Q. An azeotropic mixture of ethanol and water is to be separated in a distillation column using benzene as an entrainer. At the column operating conditions, two liquid phases are formed on a tray. The degree(s) of freedom of the system for the choice of intensive properties at equilibrium is(are) Ans: 1 to 1
Q. A fiberboard sheet (1.5 m × 2.0 m × 15 mm) is being dried by suspending it horizontally in a current of hot, dry air. The edges are insulated so that drying takes place only from the top and bottom surfaces. The wet sheet weighing 16 kg with initial moisture content of 60% loses
Q. A binary distillation column is designed by McCabe-Thiele method to get a distillate mole fraction of 0.9. The enriching section operating line has an intercept with y-axis at 0.3 mole fraction. The ratio of liquid to vapour molar flow rate in the enriching section is Ans: 0.65 to 0.68
Q. It is decided to extract A from a feed containing 20 mol% A and 80 mol% B in two ideal cross-current stages as shown below, using equal amount of pure solvent C in each stage. Components B and C are immiscible. 60% of A in the feed is extracted in Stage 1. The equilibrium
Q. The elementary second-order liquid phase reaction A + B → C + D is carried out in an isothermal plug flow reactor of 2 m3 volume. The inlet volumetric flow rate is 10 m3/h. The initial concentrations of both A and B are 2 kmol/m3. The rate constant is given as 2.5 m3 kmol-1
Q. A CSTR and a PFR of equal volume are connected in series as shown below to carry out a first-order, isothermal, liquid phase reaction The rate constant is 0.2 s-1. The space-time is 5 s for both the reactors. The overall fractional conversion of A is Ans: 0.80 to 0.84
Q. At a shear rate of 10 s-1, the apparent viscosity of a non-Newtonian liquid was found to be 1 Pa s. At a shear rate of 100 s-1, the apparent viscosity of the same liquid was found to be 0.5 Pa s. If the liquid follows power law behavior, the apparent viscosity (in Pa
