Steady state equimolal counter diffusion is encountered in (A) Separation of a binary mixture by distillation (B) Absorption of NH3 from air by water (C) All liquid-liquid diffusion systems (D) All liquid-solid diffusion systems

Steady state equimolal counter diffusion is encountered in

(A) Separation of a binary mixture by distillation

(B) Absorption of NH3

from air by water

(C) All liquid-liquid diffusion systems

(D) All liquid-solid diffusion systems


by

1 Answer

Answer :

(A) Separation of a binary mixture by distillation

by

Related questions

Pick out the correct statement. (A) Higher hold up of the solid in the rotary dryer results in better exposure of the solids to the gas (B) The 'Hatta number' is important in problems involving gas absorption without chemical reaction (C) For a non-reacting binary mixture of ideal gases, the partial pressure distribution of both components is linear in the case of steady state equimolal counter-diffusion (D) Total reflux in case of distillation operation requires infinite number of plates for a binary system separation

Description : Pick out the correct statement. (A) Higher hold up of the solid in the rotary dryer results in better exposure of the solids to the gas (B) The 'Hatta number' is ... reflux in case of distillation operation requires infinite number of plates for a binary system separation

Last Answer : (C) For a non-reacting binary mixture of ideal gases, the partial pressure distribution of both components is linear in the case of steady state equimolal counter-diffusion

Steady state equimolal counter diffusion occurs in case of (A) Leaching (B) Absorption (C) Binary phase distillation (D) Liquid-liquid extraction

Description : Steady state equimolal counter diffusion occurs in case of (A) Leaching (B) Absorption (C) Binary phase distillation (D) Liquid-liquid extraction

Last Answer : (C) Binary phase distillation

The value of NA/(NA + NB), for steady state equimolal counter diffusion of two gases 'A' and 'B' is (A) 1 (B) ∞ (C) 0.5

Description : The value of NA/(NA + NB), for steady state equimolal counter diffusion of two gases 'A' and 'B' is (A) 1 (B) ∞ (C) 0.5

Last Answer : (B) ∞

Binary distillation involves the mass transfer by __________ at the gas￾liquid interface. (A) Unidirectional diffusion from liquid to gas phase (B) Unidirectional diffusion from gas to liquid phase (C) Either 'a' or 'b' (D) A counter diffusion at an almost equal molar rate

Description : Binary distillation involves the mass transfer by __________ at the gas￾liquid interface. (A) Unidirectional diffusion from liquid to gas phase (B) Unidirectional diffusion from gas to liquid phase (C) Either 'a' or 'b' (D) A counter diffusion at an almost equal molar rate

Last Answer : (D) A counter diffusion at an almost equal molar rate

Pick out the wrong statement. (A) The mole fraction of solute is directly proportional to the molality of a 'dilute' solution (B) For a non-reacting binary mixture of ideal gases, the partial pressure distribution of both components is nonlinear in the case of steady state unimolal unidirectional diffusion (C) Azeotropes obey Raoult's law at all temperature (D) The relative volatility of a binary mixture at the Azeotropic composition is 1

Description : Pick out the wrong statement. (A) The mole fraction of solute is directly proportional to the molality of a 'dilute' solution (B) For a non-reacting binary mixture of ideal gases, the partial ... at all temperature (D) The relative volatility of a binary mixture at the Azeotropic composition is 1

Last Answer : (C) Azeotropes obey Raoult's law at all temperature

The-relative volatility for separation of a non-ideal binary mixture by distillation should be (A) 0 (B) 1 (C) > 1 (D) < 1

Description : The-relative volatility for separation of a non-ideal binary mixture by distillation should be (A) 0 (B) 1 (C) > 1 (D) < 1

Last Answer : (C) > 1

Pick out the wrong statement. (A) The Reynolds analogy for mass transfer is given by Lewis relation and is applicable, when Schmidt number is one (B) Sherwood number for flow in pipes can be expressed as the ratio of the concentration gradient at wall to the overall concentration difference (C) According to film theory for equimolar counter diffusion, the mass transfer coefficient is given by DAB(B)P - 3, Q - 2 (D) The z-component of the total mass flux of a component A in binary mixture of A and B is given by - Dab'.dCA/dz

Description : Pick out the wrong statement. (A) The Reynolds analogy for mass transfer is given by Lewis relation and is applicable, when Schmidt number is one (B) Sherwood number for flow in pipes can be expressed ... flux of a component A in binary mixture of A and B is given by - Dab'.dCA/dz

Last Answer : (C) According to film theory for equimolar counter diffusion, the mass transfer coefficient is given by DAB(B)P - 3, Q - 2

Separation of a mixture of two gases by absorption in the liquid solvent depends upon the difference in their (A) Viscosity (B) Density (C) Solubility (D) Relative volatility

Description : Separation of a mixture of two gases by absorption in the liquid solvent depends upon the difference in their (A) Viscosity (B) Density (C) Solubility (D) Relative volatility

Last Answer : (C) Solubility

Gibbs-Duhem equation (A) States that n1dμ1 + n2dμ2 + ....njdμj = 0, for a system of definite composition at constant temperature and pressure (B) Applies only to binary systems (C) Finds no application in gas-liquid equilibria involved in distillation (D) None of these

Description : Gibbs-Duhem equation (A) States that n1dμ1 + n2dμ2 + ....njdμj = 0, for a system of definite composition at constant temperature and pressure (B) Applies only to binary systems (C) Finds no application in gas-liquid equilibria involved in distillation (D) None of these

Last Answer : (A) States that n1dμ1 + n2dμ2 + ....njdμj = 0, for a system of definite composition at constant temperature and pressure

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

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

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 (above the minimum reflux ratio), the fixed cost of the distillation column first increases and then decreases (C) In Ponchon-Savarit method of no. of theoretical plate determination, the stripping and rectifying operating lines are vertical at total reflux (D) Kremser-Brown-Souder's equation is used to calculate the efficiency of a plate tower

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

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 non￾ideal binary system by distillation (B) A sharp decrease in pressure drop is an indication of flooding in a distillation coloumn (C) Solvent used in extractive distillation should be of high volatility (D) Flash distillation is suitable for separating components which have very close boiling temperature

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 non￾ideal binary system by distillation

In an operating distillation column, the (A) Vapors and liquids are at their dew point and bubble point respectively (B) Driving force for the liquid flow is its specific weight (C) Driving force for the vapor flow is the pressure drop, as the pressure decreases gradually from the bottom to the top of the column (D) Highest temperature is encountered at the top of the column

Description : In an operating distillation column, the (A) Vapors and liquids are at their dew point and bubble point respectively (B) Driving force for the liquid flow is its specific weight (C) Driving force for ... bottom to the top of the column (D) Highest temperature is encountered at the top of the column

Last Answer : (C) Driving force for the vapor flow is the pressure drop, as the pressure decreases gradually from the bottom to the top of the column

__________ is the separation technique used for desalination of sea water.(A) Thermal diffusion (B) Reverse osmosis (C) Adsorption (D) Absorption

Description : __________ is the separation technique used for desalination of sea water. (A) Thermal diffusion (B) Reverse osmosis (C) Adsorption (D) Absorption

Last Answer : (B) Reverse osmosis

Pick out the wrong statement. (A) An ideal liquid or solid solution is defined as one in which each component obeys Raoult's law (B) If Raoult's law is applied to one component of a binary mixture; Henry's law or Raoult's law is applied to the other component also (C) Henry's law is rigorously correct in the limit of infinite dilution (D) None of these

Description : Pick out the wrong statement. (A) An ideal liquid or solid solution is defined as one in which each component obeys Raoult's law (B) If Raoult's law is applied to one component of a binary mixture; ... also (C) Henry's law is rigorously correct in the limit of infinite dilution (D) None of these

Last Answer : (D) None of these

__________ is used as an 'entrainer' for the separation of acetic acid￾water mixture by distillation. (A) Furfural (B) Benzol (C) Butyl acetate (D) Hexane

Description : __________ is used as an 'entrainer' for the separation of acetic acid￾water mixture by distillation. (A) Furfural (B) Benzol (C) Butyl acetate (D) Hexane

Last Answer : (C) Butyl acetate

When the mixture to be distilled has a very high boiling point and the product material is heat sensitive, the separation technique to be used is __________ distillation. (A) Continuous (B) Steam (C) Azeotropic (D) None of these

Description : When the mixture to be distilled has a very high boiling point and the product material is heat sensitive, the separation technique to be used is __________ distillation. (A) Continuous (B) Steam (C) Azeotropic (D) None of these

Last Answer : (B) Steam

Which of the following can be regarded as gas so that gas laws could be applicable, within the commonly encountered temperature limits.  (a) 02, N2, steam, C02  (b) Oz, N2, water vapour  (c) S02, NH3, C02, moisture  (d) 02, N2, H2, air  (e) steam vapours, H2, C02.

Description : Which of the following can be regarded as gas so that gas laws could be applicable, within the commonly encountered temperature limits.  (a) 02, N2, steam, C02  (b) Oz, N2, water vapour  (c) S02, NH3, C02, moisture  (d) 02, N2, H2, air  (e) steam vapours, H2, C02.

Last Answer : Answer : d

For which of the following unit operations, Lewis number is ofsignificance?(A) Adsorption(B) Binary distillation(C) Gas absorption(D) Humidification

Description : For which of the following unit operations, Lewis number is ofsignificance? (A) Adsorption (B) Binary distillation (C) Gas absorption (D) Humidification

Last Answer : (D) Humidification

The Hatta number is important in (A) Multi-component distillation (B) Binary distillation (C) Gas absorption without chemical reaction (D) Gas absorption with chemical reaction

Description : The Hatta number is important in (A) Multi-component distillation (B) Binary distillation (C) Gas absorption without chemical reaction (D) Gas absorption with chemical reaction

Last Answer : (D) Gas absorption with chemical reaction

A distillation column with N plates is being operated under normal conditions. At some point of time, the operation is shifted to total reflux condition (i.e., no product and residue are being withdrawn and feed to the column is stopped). At the new steady state, (A) Composition of vapors and that of liquid do not vary throughout the column (B) Reboiler load and condenser load are minimum (C) The top and bottom compositions are unchanged with and without total reflux (D) The top and bottom compositions correspond to the maximum enrichment available

Description : A distillation column with N plates is being operated under normal conditions. At some point of time, the operation is shifted to total reflux condition (i.e., no product and residue are ... and without total reflux (D) The top and bottom compositions correspond to the maximum enrichment available

Last Answer : (D) The top and bottom compositions correspond to the maximum enrichment available

The equation, NA = (DAB . Pt /RTZ . PBM) (PA1 - PA2 ) is for (A) Fick's second law of diffusion (B) Steady state diffusion for stagnant case (C) Liquid M.T.C. by Higbie penetration theory (D) None of these

Description : The equation, NA = (DAB . Pt /RTZ . PBM) (PA1 - PA2 ) is for (A) Fick's second law of diffusion (B) Steady state diffusion for stagnant case (C) Liquid M.T.C. by Higbie penetration theory (D) None of these

Last Answer : (B) Steady state diffusion for stagnant case

Components, having widely different boiling point in a binary mixture, can be separated using __________ distillation. (A) Molecular (B) Extractive (C) Steam (D) Simple

Description : Components, having widely different boiling point in a binary mixture, can be separated using __________ distillation. (A) Molecular (B) Extractive (C) Steam (D) Simple

Last Answer : (D) Simple

Pick out the wrong statement. (A) Constant pressure distillation cannot separate an Azeotropic mixture (B) Relative volatility of a binary mixture changes appreciably with the minor change in temperature (C) The relative volatility of a binary mixture at Azeotropic composition is unity (D) Flash distillation is practised on wide spread scale in petroleum refinery

Description : Pick out the wrong statement. (A) Constant pressure distillation cannot separate an Azeotropic mixture (B) Relative volatility of a binary mixture changes appreciably with the minor change in ... unity (D) Flash distillation is practised on wide spread scale in petroleum refinery

Last Answer : (B) Relative volatility of a binary mixture changes appreciably with the minor change in temperature

A binary mixture of benzene and cyclohexane is separated by (A) Flash vaporisation (B) Extractive distillation (C) Solvent extraction (D) Ordinary distillation

Description : A binary mixture of benzene and cyclohexane is separated by (A) Flash vaporisation (B) Extractive distillation (C) Solvent extraction (D) Ordinary distillation

Last Answer : (B) Extractive distillation

For a binary mixture with low relative volatility, (A) Use steam distillation (B) Use molecular distillation (C) Use high pressure distillation (D) An azeotrope may be formed during distillation

Description : For a binary mixture with low relative volatility, (A) Use steam distillation (B) Use molecular distillation (C) Use high pressure distillation (D) An azeotrope may be formed during distillation

Last Answer : (D) An azeotrope may be formed during distillation

For a binary mixture distillation process, the degree of freedom is 2. However, if the pressure is fixed in this process, the number of independent variables in this process will be (A) 1 (B) 0 (C) 2 (D) 3

Description : For a binary mixture distillation process, the degree of freedom is 2. However, if the pressure is fixed in this process, the number of independent variables in this process will be (A) 1 (B) 0 (C) 2 (D) 3

Last Answer : (A) 1

According to the Fenske equation, what will be the minimum number of plates required in a distillation column to separate an equimolar binary mixture of components A and B into an overhead fraction containing 99 mol% A and a bottom fraction containing 98 mol% B ? Assume that relative volatility (αAB = 2) does not change appreciably in the column. (A) 5 (B) 9 (C) 12 (D) 28

Description : According to the Fenske equation, what will be the minimum number of plates required in a distillation column to separate an equimolar binary mixture of components A and B into an overhead fraction containing 99 mol% A and a ... in the column. (A) 5 (B) 9 (C) 12 (D) 28

Last Answer : (C) 12

What property of substance does distillation used as basis for separation of components of a mixture?

Description : What property of substance does distillation used as basis for separation of components of a mixture?

Last Answer : Different materials have different boiling points.

Pick out the wrong statement: (A) Reboiler is not used in open steam distillation (B) The separation of solutes of different molecular sizes in a liquid solution by use of a suitable membrane is called dialysis (C) Freeze drying is used for the drying of fish (D) Fenske-Underwood equation is used for calculating theoretical number of plates in a distillation column at normal operating reflux condition

Description : Pick out the wrong statement: (A) Reboiler is not used in open steam distillation (B) The separation of solutes of different molecular sizes in a liquid solution by use of a ... is used for calculating theoretical number of plates in a distillation column at normal operating reflux condition

Last Answer : (D) Fenske-Underwood equation is used for calculating theoretical number of plates in a distillation column at normal operating reflux condition

Pick out the wrong statement. (A) Critical moisture content is not a property of the material itself (B) A sharp increase in pressure drop gives an indication of the flooding in a distillation column (C) Separation of components is not possible in liquid extraction, if selectivity is unity (D) Dehydration of ethyl alcohol is most economically done by molecular distillation at very high vacuum

Description : Pick out the wrong statement. (A) Critical moisture content is not a property of the material itself (B) A sharp increase in pressure drop gives an indication of the flooding in a ... unity (D) Dehydration of ethyl alcohol is most economically done by molecular distillation at very high vacuum

Last Answer : (D) Dehydration of ethyl alcohol is most economically done by molecular distillation at very high vacuum

Flash distillation is (A) Same as differential distillation (B) Used for multi-component systems like crude refining (C) Same as simple distillation (D) Most useful for handling binary systems

Description : Flash distillation is (A) Same as differential distillation (B) Used for multi-component systems like crude refining (C) Same as simple distillation (D) Most useful for handling binary systems

Last Answer : (B) Used for multi-component systems like crude refining

Pick out the wrong statement. (A) The binary diffusivity in liquids is of the order of 10 -5 cm2 /sec (B) Molecular diffusion in solid is much faster than that in liquids (C) Particles movement from higher concentration to lower concentration takes place in diffusion process (D) According to Poiseuille's law, the permeability decreases with increase in temperature for flow of a gas through a given capillary

Description : Pick out the wrong statement. (A) The binary diffusivity in liquids is of the order of 10 -5 cm2 /sec (B) Molecular diffusion in solid is much faster than that in liquids ( ... Poiseuille's law, the permeability decreases with increase in temperature for flow of a gas through a given capillary

Last Answer : (B) Molecular diffusion in solid is much faster than that in liquids

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 small columns, local efficiency is larger than Murphree efficiency; in large columns local efficiency is smaller than Murphree efficiency (C) For Laminar flow over a plate of length L, the local mass transfer co￾efficient 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 (D) The concentration and hydrodynamic boundary layers over a flat plate are of equal thickness, if Schmidt number is equal to unity

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 co￾efficient 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

Pick out the wrong statement. (A) With decrease in feed temperature, the number of plates required for binary distillation decreases for a given ‘L/V’ ratio (B) The extraction per unit of total height for a short packed column is more effective than for a tall column, in case of liquid-liquid extraction(C) Natural draft cooling towers are made of ferroconcrete and its cross￾section is wider at the bottom(D) Vander wall adsorption is also called chemisorption

Description : Pick out the wrong statement. (A) With decrease in feed temperature, the number of plates required for binary distillation decreases for a given L/V' ratio (B) The extraction per unit ... and its cross￾section is wider at the bottom (D) Vander wall adsorption is also called chemisorption

Last Answer : (D) Vander wall adsorption is also called chemisorption

__________ temperature is the steady state temperature attained by a small amount of liquid evaporating into a large quantity of unsaturated gas￾vapor mixture. (A) Dry bulb (B) Wet bulb (C) Dew point (D) None of these

Description : __________ temperature is the steady state temperature attained by a small amount of liquid evaporating into a large quantity of unsaturated gas￾vapor mixture. (A) Dry bulb (B) Wet bulb (C) Dew point (D) None of these

Last Answer : (B) Wet bulb

Steady state temperature reached by a small amount of liquid evaporating into a large amount of unsaturated vapour-gas mixture is called the __________ temperature. (A) Dry-bulb (B) Wet-bulb (C) Dew point (D) Adiabatic saturation

Description : Steady state temperature reached by a small amount of liquid evaporating into a large amount of unsaturated vapour-gas mixture is called the __________ temperature. (A) Dry-bulb (B) Wet-bulb (C) Dew point (D) Adiabatic saturation

Last Answer : (B) Wet-bulb

Heat sensitive materials with very high latent heat of vaporisation may be economically separated using (A) Liquid extraction (B) Distillation (C) Evaporation (D) Absorption

Description : Heat sensitive materials with very high latent heat of vaporisation may be economically separated using (A) Liquid extraction (B) Distillation (C) Evaporation (D) Absorption

Last Answer : (A) Liquid extraction

The recovery of penicillin from the acidified fermentation broth is done by (A) Distillation (B) Evaporation (C) Absorption (D) Liquid extraction

Description : The recovery of penicillin from the acidified fermentation broth is done by (A) Distillation (B) Evaporation (C) Absorption (D) Liquid extraction

Last Answer : (D) Liquid extraction

In case of liquid-liquid binary diffusion, diffusivity of one constituent into another is not dependent on the (A) Temperature and pressure (B) Concentration (C) Nature of the constituents (D) None of these

Description : In case of liquid-liquid binary diffusion, diffusivity of one constituent into another is not dependent on the (A) Temperature and pressure (B) Concentration (C) Nature of the constituents (D) None of these

Last Answer : (D) None of these

Separation of two or more components of a liquid solution cannot beachieved by (A) Fractional crystallisation (B) Liquid extraction (C) Absorption (D) Evaporation

Description : Separation of two or more components of a liquid solution cannot beachieved by (A) Fractional crystallisation (B) Liquid extraction (C) Absorption (D) Evaporation

Last Answer : (C) Absorption

Separation of __________ employs gaseous diffusion process. (A) N2 and O2 from air (B) Isotopes of uranium (C) Isotopes of helium (D) SO2 and air

Description : Separation of __________ employs gaseous diffusion process. (A) N2 and O2 from air (B) Isotopes of uranium (C) Isotopes of helium (D) SO2 and air

Last Answer : (B) Isotopes of uranium

With increase in the liquid flow rate at a fixed gas velocity in a randomly packed counter current gas-liquid absorption column, the gas pressure drop (A) Decreases (B) Remains unchanged (C) Increases (D) Decreases exponentially

Description : With increase in the liquid flow rate at a fixed gas velocity in a randomly packed counter current gas-liquid absorption column, the gas pressure drop (A) Decreases (B) Remains unchanged (C) Increases (D) Decreases exponentially

Last Answer : (C) Increases

Separation of a suspension or slurry into a supernatant clear liquid (free from particles) and a thick sludge containing a high concentration of solid is called (A) Classification (B) Sedimentation (C) Clarification (D) Decantation

Description : Separation of a suspension or slurry into a supernatant clear liquid (free from particles) and a thick sludge containing a high concentration of solid is called (A) Classification (B) Sedimentation (C) Clarification (D) Decantation

Last Answer : (B) Sedimentation

Separation of solid suspended in liquid into a supernatant clear liquid and a denser slurry employs a process termed as the (A) Coagulation (B) Flocculation (C) Sedimentation (D) Clarification

Description : Separation of solid suspended in liquid into a supernatant clear liquid and a denser slurry employs a process termed as the (A) Coagulation (B) Flocculation (C) Sedimentation (D) Clarification

Last Answer : (C) Sedimentation

Stage efficiency in a leaching process depends on the (A) Time of contact between the solid and the solution (B) Rate of diffusion of the solute through the solid and into the liquid (C) Both (A) and (B) (D) Vapour pressure of the solution

Description : Stage efficiency in a leaching process depends on the (A) Time of contact between the solid and the solution (B) Rate of diffusion of the solute through the solid and into the liquid (C) Both (A) and (B) (D) Vapour pressure of the solution

Last Answer : (C) Both (A) and (B)

The rate of solid-liquid extraction is limited by the (A) Phase change of the solute as it dissolves in the solvent (B) Diffusion of the solute through the solvent in the pores to the outside of the particle (C) Diffusion of the solute from the solution in contact with the particle to the main bulk of the solution (D) All 'a', 'b' & 'c'

Description : The rate of solid-liquid extraction is limited by the (A) Phase change of the solute as it dissolves in the solvent (B) Diffusion of the solute through the solvent in the pores to the outside of the particle (C) ... contact with the particle to the main bulk of the solution (D) All 'a', 'b' & 'c'

Last Answer : (D) All 'a', 'b' & 'c'

The value of NA/(NA + NB) for steady state molecular diffusion of gas 'A' through non-diffusing gas 'B' is (A) 1 (B) ∞ (C) 0.5 (D) 2

Description : The value of NA/(NA + NB) for steady state molecular diffusion of gas 'A' through non-diffusing gas 'B' is (A) 1 (B) ∞ (C) 0.5 (D) 2

Last Answer : (A) 1