Separation of two volatile liquids by distillation makes use of their
(A) Selectivity
(B) Relative volatility
(C) Solubility
(D) Density difference
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
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
Description : The reciprocal of stripping factor is termed as (A) Selectivity index (B) Relative volatility (C) Absorption factor (D) Murphree efficiency
Last Answer : (C) Absorption factor
Description : The expression, y(1 - x)/x(1 - y) is for (A) Absorption factor (B) Relative volatility (C) Selectivity (D) Murphree efficiency
Last Answer : (B) Relative volatility
Description : Distillation at reduced pressure is used for liquids which (a) Have high boiling points (b) Have low boiling points (c) Have high volatility (d) Decompose before their boiling points
Last Answer : Ans:(d)
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 : 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
Description : Fugacity is a measure of the (A) Escaping tendencies of the same substance in different phases of a system (B) Relative volatility of a mixture of two miscible liquids (C) Behaviour of ideal gases (D) None of these
Last Answer : (A) Escaping tendencies of the same substance in different phases of a system
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
Description : Solvent used in extractive distillation (A) Changes the relative volatility of the original components (B) Should be of high volatility (C) Should form azeotropes with the original components (D) All (A), (B) and (C)
Last Answer : (A) Changes the relative volatility of the original components
Description : In extractive distillation, solvent is (A) Added to alter the relative volatility of the mixture (B) Of high volatility (C) Present in overhead stream (D) Of high viscosity to give high tray efficiency
Last Answer : (A) Added to alter the relative volatility of the mixture
Description : Solvent used in extractive distillation (A) Is of low volatility (B) Forms a low boiling azeotrope (C) Forms a high boiling azeotrope (D) Does not alter the relative volatility of the original components
Last Answer : (B) Forms a low boiling azeotrope
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)
Last Answer : (D) All (A), (B) and (C)
Description : If the amount of the steam used in steam distillation is increased, the temperature of distillation (A) Increases (B) Decreases (C) Remains unchanged (D) Depends on relative volatility
Last Answer : (B) Decreases
Description : Entrainer used in Azeotropic distillation should (A) Form a low boiling azeotrope with one of the constituents of the mixture (B) Form a new azeotrope of low relative volatility with one of the ... (C) Have high latent heat of vaporisation (D) Have high viscosity to provide high tray efficiency
Last Answer : (A) Form a low boiling azeotrope with one of the constituents of the mixture
Description : Fenske equation for determining the minimum number of theoretical stages in distillation column holds good, when the (A) Relative volatility is reasonably constant (B) Mixture (to be separated) ... (to be separated) shows positive deviation from ideality (D) Multi-component distillation is involved
Last Answer : (A) Relative volatility is reasonably constant
Description : In case of __________ distillation, a solvent is added to alter the relative volatility of the mixture to be separated. (A) Molecular (B) Azeotropic (C) Extractive
Last Answer : (C) Extractive
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
Description : High pressure at the bottom of a distillation tower handling heat sensitive materials results in (A) Thermal decomposition of bottoms (B) Increased relative volatility (C) Erosion of the tower (D) Very efficient operation
Last Answer : (A) Thermal decomposition of bottoms
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
Description : In a binary system, separation is very efficient, when the relative volatility is (A) 1 (B) > 1 (C) < 1 (D) 0.5
Last Answer : (B) > 1
Description : _________ is defined as the geometric mean of the relative rejections and the relative recoveries of two minerals. (A) Separation efficiency (B) Selectivity index (C) Concentration ratio (D) None of these
Last Answer : (B) Selectivity index
Description : Steam distillation is used for separation of high boiling (A) Substances from non-volatile impurities (B) Volatile impurity from still higher boiling substances (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) and (B)
Description : Give any two applications of simple distillation.Describe method of separation of two immiscible liquids.
Last Answer : Applications of simple distillation(0.5 2) 1) Preparation of distilled water and water for injection. 2)Recovery of alcohol in preparation of dry extracts 3)Many volatile oils and ... proportion The distillate can be collected in Florentine receiver for separation of oil & water.
Description : Washability curve based on float and sink test enables an assessment to be made of the possibility of cleaning a coal fraction based on the (A) Density separation (B) Differential wettability (C) Size (D) Volatile matter content
Last Answer : (A) Density separation
Description : In Gas-Liquid Chromatography, some of the samples need to be derivatized in order to increase their (A) volatility (B) solubility (C)thermal conductivity (D) polarizability
Last Answer : (D) polarizability
Description : A gravity decanter is meant for the separation of two __________ density. (A) Immiscible liquids of different (B) Miscible liquids of different (C) Immiscible liquids of same (D) Miscible liquids of same
Last Answer : (A) Immiscible liquids of different
Description : In which of the following unit operations, the selectivity is an important parameter? (A) Distillation (B) Solvent extraction (C) Absorption (D) None of these
Last Answer : (B) Solvent extraction
Description : Polar organic compounds are normally used as separating agents for the azeotropic and extractive distillation. Which of the following is the most important factor to be considered for the choice of the separating agent ... ? (A) Cost (B) Availability (C) Toxicity (D) Selectivity
Last Answer : (D) Selectivity
Description : Pick out the correct statement. (A) In case of liquid-liquid extraction, no separation is possible, if the selectivity of the solvent used is unity (B) With increase in temperature, the selectivity of the solvent used ... in solvent extraction is unity at the plait point (D) All (A), (B) and (C)
Description : In liquid extraction, if the selectivity is unity, then (A) Separation of the constituents is the most effective (B) No separation will occur (C) Amount of solvent required will be minimum (D) Solvent flow rate should be very low
Last Answer : (B) No separation will occur
Description : A plait point is the point on the solubility curve, where the tie line reduces to a point. What is the number of plait point for a ternary system containing two pairs of partially miscible liquids? (A) 0 (B) 1 (C) 2 (D) 3
Last Answer : (A) 0
Description : With increase in temperature, the mutual solubility of two liquids (A) Increases (B) Decreases (C) Remains unchanged (D) Decreases exponentially
Last Answer : (A) Increases
Description : Critical solution temperature (or the con-solute temperature) for partially miscible liquids (e.g., phenol-water) is the minimum temperature at which (A) A homogeneous solution (say of phenol water) is ... a decreasing trend (C) Two liquids are completely separated into two layers (D) None of these
Last Answer : (A) A homogeneous solution (say of phenol water) is formed
Description : With increase in temperature, the solubility of gases in liquids, at fixed pressure (A) Increases (B) Decreases (C) Remain same (D) Either (A) or (B), depends on the system
Description : When acetone is added in a two layer mixture of methyl isobutyl ketone and water at 30°C, the acetone distributes between the two layers and the composition of the layer follows two solubility curves. For this system ... at the concentration of the plait point (D) All (A), (B) and (C
Last Answer : (D) All (A), (B) and (C
Description : Pick out the wrong statement. (A) In solvent extraction, the distribution co-efficient should be as large as possible for solvent economy (B) With increase in pressure, the solubility of ... in distillation column (D) The capacity of a distillation column is maximum at total reflux
Last Answer : (D) The capacity of a distillation column is maximum at total reflux
Description : The hygrometer is an instrument to measure (a) the relative density of liquids (b) the purity of milk (c) relative humidity (d) atmospheric pressure
Last Answer : Ans:(c)
Description : For a binary mixture with low relative volatility, continuous rectification to get pure products will require (A) Low reflux ratio (B) Less number of trays (C) Small cross-section column (D) High reflux ratio
Last Answer : (D) High reflux ratio
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
Description : With increase in pressure, the relative volatility for a binary system (A) Increases (B) Decreases (C) Remains same
Description : Relative volatility does not change appreciably with the change in (A) Temperature (B) Vapour pressure of either component (C) Total pressure (D) None of these
Last Answer : (A) Temperature
Description : When the liquid phase and vapour phase of a binary system obeys Raoult's and Dalton's law respectively, the relative volatility is the ratio of (A) Vapour pressure of component A to that of ... to the partial pressure of A (D) Partial pressure of component A to the total pressure
Last Answer : (A) Vapour pressure of component A to that of component B
Description : The slope of 9-line is determined by the (A) Reflux ratio (B) Plate efficiency to be achieved (C) Thermal condition of the feed (D) Relative volatility
Last Answer : (C) Thermal condition of the feed
Description : Relative volatility varies with the concentration of component for an ideal solution. The relative volatility of a binary mixture may be defined as the ratio of vapor pressure of component 'A' to that of ... law (D) Vapor phase obeys Dalton's law and liquid phase obeys Raoult's law
Last Answer : (D) Vapor phase obeys Dalton's law and liquid phase obeys Raoult's law
Description : The relative volatility of a binary mixture at the Azeotropic composition is (A) 1 (B) > 1 (C) 0 (D) ∞
Last Answer : (D) ∞
Description : The relative volatility of a binary mixture at constant temperature __________ the total pressure. (A) Decreases with increase in (B) Increases with increase in (C) Is independent of (D) None of these
Last Answer : (A) Decreases with increase in
Description : Which of the following may prove unsuitable for filtering volatile liquids? (A) Pressure filter (B) Gravity filter (C) Centrifugal filter (D) Vacuum filter
Last Answer : (D) Vacuum filter
Description : Inside the distillation column, the (A) Driving force for the vapour flow is the pressure drop (B) Liquids are not always at their bubble points (C) Pressure increases gradually from bottom to the top of the column (D) None of these
Last Answer : (A) Driving force for the vapour flow is the pressure drop
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