McCabe-Thiele method
(A) Uses molal units for material and energy balance
(B) Uses weight fractions to express liquid and vapour composition
(C) Can use any type of units
(D) Is more accurate than Ponchon-Savarit method
Description : Design calculation for multiple component distillation is done by (A) Ponchon-Savarit method (B) McCabe-Thiele method (C) Enthalpy concentration method (D) Tray to tray calculations
Last Answer : (D) Tray to tray calculations
Description : Which of the following assumes constant molal vaporisation and overflow? (A) McCabe-Thiele method (B) Ponchan-Savarit method (C) Enthalpy concentration method (D) Plate absorption column
Last Answer : (A) McCabe-Thiele method
Description : Ponchon-Savarit method analyses the fractional equipment based on (A) Enthalpy balance only (B) Material balance only (C) Both enthalpy and material balances (D) The assumption of constant molal-overflow
Last Answer : (C) Both enthalpy and material balances
Description : Pick out the correct statement. (A) Ponchan-Savarit method is more accurate than McCabe-Thiele method to determine the number of theoretical stages required for the separation of ... Flash distillation is suitable for separating components which have very close boiling temperature
Last Answer : (A) Ponchan-Savarit method is more accurate than McCabe-Thiele method to determine the number of theoretical stages required for the separation of nonideal binary system by distillation
Description : In distillation column design, the McCabe-Thiele procedure is inadequate and a Ponchan-Savarit procedure is needed, when (A) Saturated feed is not used (B) An azeotrope forms (C) The latent ... vaporisation of the more and less volatile components are greatly different (D) A total condenser is used
Last Answer : (D) A total condenser is used
Description : Pick out the wrong statement. (A) In the McCabe-Thiele diagram for binary distillation, vertical feed line represents saturated liquid feed and horizontal feed line represents saturated vapour feed (B) In ... layers over a flat plate are of equal thickness, if Schmidt number is equal to unity
Last Answer : (C) For Laminar flow over a plate of length L, the local mass transfer coefficient at a distance L from the leading edge is 1.5 × 10 -2m/s. Then the average mass transfer co-efficient for the plate is 2 × 10 -2m/s
Description : If f = moles of vapour present per mole of feed, then the slope of feed line is (McCabe-Thiele method) (A) (1 - f)/f (B) - (f - 1)/f (C) -1/f (D) -f/(1 - f)
Last Answer : (C) -1/f
Description : Pick out the correct statement. (A) The slope of the stripping line is always less than unity (B) For a given separation in a binary distillation column, with increase in reflux ratio ( ... (D) Kremser-Brown-Souder's equation is used to calculate the efficiency of a plate tower
Last Answer : C) In Ponchon-Savarit method of no. of theoretical plate determination, the stripping and rectifying operating lines are vertical at total reflux
Description : McCabe-Thiele method of binary distillation does not assume that the (A) Sensible heat changes are negligible compared with latent heat changes (B) Molar latent heats of all components are equal (C) Heat of mixing is negligible (D) None of these
Last Answer : (D) None of these
Description : In McCabe-Thiele method of theoretical plate calculation for a distillation column, the operating lines of stripping and rectifying sections coincide with the diagonal at __________ reflux. (A) Total (B) Minimum (C) Operating (D) Maximum permissible
Last Answer : (A) Total
Description : Pick out the wrong statement. (A) Different solids have different equilibrium moisture curves (B) Total condenser or reboiler is considered equivalent to one theoretical plate in McCabe-Thiele method of ... (D) Even a forced draft cooling tower cannot cool water below the wet bulb temperature
Last Answer : (C) Heat removal load on cooler remains constant, even with increase of the reflux ratio in a distillation column
Description : In McCabe-Thiele method, at infinite reflux ratio (A) The overhead product is minimum (B) Both the operating lines coincide with diagonal (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (A) The overhead product is minimum
Description : In McCabe-Thiele method, at infinite reflux ratio (A) Number of plates is maximum (B) Overhead product is maximum (C) Both the operating lines coincide with the diagram (D) None of these
Last Answer : (C) Both the operating lines coincide with the diagram
Description : At 60° C, vapour pressure of methanol and water are 84.562 kPa and 19.953 kPa respectively. An aqueous solution of methanol at 60° C exerts a pressure of 39.223 kPa; the liquid phase and vapour phase mole ... respectively. Activity co-efficient of methanol is (A) 1.572 (B) 1.9398 (C) 3.389
Last Answer : (A) 1.572
Description : In Azeotropic mixture, the equilibrium vapour composition is (A) More than liquid composition (B) Less than liquid composition (C) Same as liquid composition (D) Independent of pressure
Last Answer : (C) Same as liquid composition
Description : Clausius-Clapeyron Equation gives accurate result, when the (A) Vapour pressure is relatively low and the temperature does not vary over wide limits (B) Vapour obeys the ideal gas law and the latent heat of ... is negligible compared with that in the vapour state (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Pick out the wrong statement. (A) The integral method of analysing kinetic data is used when the data is scattered (B) The differential method of analysing kinetic data requires more accurate ... less than one for identical feed composition, flow rate, conversion and for all positive reaction orders
Last Answer : (C) When the reaction rate is independent of temperature, the reaction is said to be of zero order
Description : A reasonably general expression for vapour-liquid phase equilibrium at low to moderate pressure is φi yi P = Yi xifi° where, Φ is a vapor fugacity component, Yiis the liquid activity co- ... and liquid composition xi only (D) Temperature, pressure, liquid composition xi and vapour composition yi
Last Answer : (C) Temperature, pressure and liquid composition xi only
Description : Which of the following unit operations makes use of Thiele-Geddes equation? (A) Liquid-liquid extraction (B) Solid-liquid extraction (C) Multi-component absorption with chemical reaction (D) Multi-component distillation
Last Answer : (D) Multi-component distillation
Description : The chemical potential for a pure substance is __________ its partial molal free energy. (A) More than (B) Less than (C) Equal to (D) Not related to
Last Answer : (C) Equal to
Description : For a multi-component system, the term chemical potential is equivalent to the (A) Molal concentration difference (B) Molar free energy (C) Partial molar free energy (D) Molar free energy change
Last Answer : (C) Partial molar free energy
Description : Gibbs free energy per mole for a pure substance is equal to the (A) Latent heat of vaporisation (B) Chemical potential (C) Molal boiling point (D) Heat capacity
Last Answer : (B) Chemical potential
Description : In case of steam distillation, the steam leaving the liquid is not completely saturated with distillate vapour, because (A) Temperature is less (B) Total pressure is less (C) Mixing of steam ... not so intimate as to result in equilibrium condition (D) Saturated steam is used for steam distillation
Last Answer : (C) Mixing of steam with the material being vaporised is not so intimate as to result in equilibrium condition
Description : Pick out the wrong statement. (A) Surface tension of a substance vanishes at critical point, as there is no distinction between liquid and vapour phases at its critical point (B) Entropy of ... is negative for exothermic reactions (D) The eccentric factor for all materials is always more than one
Last Answer : (D) The eccentric factor for all materials is always more than one
Description : The McCabe ΔL law states that the (A) Molar heats of vaporisation of components are nearly equal (B) Linear crystal growth rate depends on the degree of super-saturation (C) Linear ... does not depend on the crystal size (D) Linear crystal growth rate depends on the crystal size
Last Answer : (C) Linear crystal growth rate does not depend on the crystal size
Description : Which of the following is NOT characteristic of a nursing research? a. Development of theories, principles, and generalizations b. Uses chaotic method of problem-solving c. Requires full skill of writing report d. Involves precise observation and accurate description
Last Answer : b. Uses chaotic method of problem-solving
Description : When liquid and vapour phases of one component system are in equilibrium (at a given temperature and pressure), the molar free energy is (A) More in vapour phase (B) More in liquid phase (C) Same in both the phases (D) Replaced by chemical potential which is more in vapour phase
Last Answer : (C) Same in both the phases
Description : What is the Thiele modulus of the solid catalysed first order reaction as shown in the bellow figure, if the pore diffusion offers negligible resistance to reaction? (A) < 5 (B) < 0.5 (C) > 1 (D) 5
Last Answer : (B) < 0.5
Description : If Thiele modulus is __________, then the pore diffusion resistance in a catalyst may be considered as negligible. (A) 0 (B) ∞ (C) < 0.5 (D) > 0.5
Last Answer : (C) < 0.5
Description : For a first order chemical reaction in a porous catalyst, the Thiele modulus is 10. The effectiveness factor is approximately equal to (A) 0 (B) 1 (C) 0.1 (D) 0.5
Last Answer : (C) 0.1
Description : Which of the following is not a dimension-less group used in catalysis? (Where, D = dispersion co-efficient, cm2 /sec.D1 = diffusion co-efficient; cm2 /sec L = length of the reactor, cm t = time, sec, v = volumetric ... (D/vL) (B) Reduced time (vt/V) (C) Thiele modulus L √(k/D1 ) (D) None of these
Description : Effectiveness factor (E) of a catalyst pellet is defined as, E = (actual rate within pore of the catalyst)/(rate if not snowed by pore diffusion), Effectiveness factor for a first order reaction is given by (where, T = Thiele modulus) (A) tan hT/T (B) tan T/T (C) tan hT/tan T (D) None of these
Last Answer : (A) tan hT/T
Description : The effectiveness factor for large value of Thiele modulus [L√(K/D1 )] of a solid catalysed first order reaction is equal to (where, L = length of the reactor, cm, D1 = diffusion co-efficient, cm2 /second). (A) L √(K/D1 ) (B) 1/[L√(K/D1 )] (C) 1 (D) ∞
Last Answer : (B) 1/[L√(K/D1 )]
Description : If two compounds have the same empirical formula but different molecular formula, they must have [MP PMT 1986] (A) Different percentage composition (B) Different molecular weights (C) Same viscosity (D) Same vapour density
Last Answer : (B) Different molecular weights
Description : Calculate the value of closing stock from the following according to Weighted Average method: 1st January, 2014: Opening balance: 50 units @ Rs. 4 Receipts: 5th January, 2014: 100 units @ Rs. 5 12th January, 2014: 200 units ... 2014: 150 units (a) Rs. 765 (b) Rs. 805 (c) Rs. 786 (d) Rs. 700
Last Answer : (c) Rs. 786
Description : Calculate the value of closing stock from the following according to LIFO method: 1st January, 2014: Opening balance: 50 units @ Rs. 4 Receipts: 5th January, 2014: 100 units @ Rs. 5 12th January, 2014: 200 units @ Rs. 4.50 ... , 2014: 150 units (a) Rs. 765 (b) Rs. 805 (c) Rs. 786 (d) Rs. 700
Last Answer : (b) Rs. 805
Description : Calculate the value of closing stock from the following according to FIFO method: 1st January, 2014: Opening balance: 50 units @ Rs. 4 Receipts: 5th January, 2014: 100 units @ Rs. 5 12th January, 2014: 200 units @ Rs. 4.50 ... , 2014: 150 units (a) Rs. 765 (b) Rs. 805 (c) Rs. 786 (d) Rs. 700
Last Answer : (a) Rs. 765
Description : Fenske-Underwood equation used for calculating the minimum number of theoretical plates in distillation column is valid for (A) Constant molal overflow (B) Total reflux (C) Constant relative volatility (D) All (A), (B) and (C)
Description : The dimension of diffusivity is same as that of the (A) Density (B) Molal concentration (C) Kinematic viscosity (D) Velocity head
Last Answer : (C) Kinematic viscosity
Description : Wetted wall tower experiment determines the (A) Molal diffusivity (B) Volumetric co-efficient (C) Mass transfer co-efficient (D) None of these
Last Answer : (C) Mass transfer co-efficient
Description : In case of non-ideal gases and liquids, the molal diffusivity (A) Varies inversely as the pressure (B) Varies directly as the pressure (C) Is independent of pressure (D) Is equal to the volumetric diffusivity
Last Answer : (C) Is independent of pressure
Description : Pick out the wrong statement (A) A horizontal line on the humidity chart indicates the temperature changes at constant molal humidity (B) When water is cooled from 80 to 70°C by exposure ... & air cannot be increased by either reducing the mixture temperature or by increasing the total pressure
Last Answer : (D) Relative saturation of unsaturated mixture of water vapor & air cannot be increased by either reducing the mixture temperature or by increasing the total pressure
Description : Humidity chart is useful for the solution of problems concerning condensation, vaporisation and air conditioning. At a given dry bulb temperature, value of humidity obtained from the humidity chart directly, is in ... (A) Molal (B) Relative (C) Percentage (D) None of these
Last Answer : (A) Mola
Description : Trouton's ratio is given by (where λb, = molal heat of vaporisation of a substance at its normal boiling point, kcal/kmol Tb = normal boiling point, °K) (A) λb/Tb (B) Tb/λb (C) √(λb/Tb) (D) √(Tb/λb)
Last Answer : (A) λb/Tb
Description : Which of the following is an extensive property of a system? (A) Heat capacity (B) Molal heat capacity (C) Pressure (D) Concentration
Last Answer : A) Heat capacity
Description : The advantage of backward feed multiple effect evaporators over forward feed units is that (A) Heat sensitive material can be handled (B) There is no additional cost of pumping ... liquid is at highest temperature (D) Equal heat transfer co-efficients exist in various effects
Last Answer : (C) Most concentrated liquid is at highest temperature
Description : Which one of the following statements is correct ? a) For water at 100o Celsius at sea level, the vapour pressure is equal to atmospheric pressure b) Surface energy (or tension) is caused by ... it both in static and in dynamic conditions d) Air is 50,000 times more compressible than water
Last Answer : c) Viscosity of a fluid is the property exhibited by it both in static and in dynamic conditions
Description : The Cyclomatic Complexity, V(G) was developed by A. Howard B. McCabe C. Boehm D. None of the above.
Last Answer : B. McCabe
Description : _____ is a white-box testing technique first proposed by Tom McCabe. a) Equivalence Partitioning b) Basis Path Testing c.) Boundary Value Analysis d) None of the above.
Last Answer : Ans : b.
Description : Routine maintenance of dry-type transformers should include ____________. A. cleaning the windings, if accessible, with a vacuum cleaner or very low pressure air B. measuring and recording the winding ... . making sure that the units are close to bulkheads or corners to protect them from damage
Last Answer : Answer: A