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
Description : With increase in pressure, the relative volatility for a binary system (A) Increases (B) Decreases (C) Remains same
Last Answer : (B) Decreases
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 : 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 : 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 : 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 : 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 : 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 relative volatility of a binary mixture at the Azeotropic composition is (A) 1 (B) > 1 (C) 0 (D) ∞
Last Answer : (D) ∞
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 : 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 : 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
Description : For a stable phase at constant pressure and temperature, the fugacity of each component in a binary system __________ as its mole fraction increases. (A) Decreases (B) Increases (C) Remain same (D) Decreases linearly
Last Answer : (B) Increases
Description : The boiling points of pure components of a binary system __________ with increase in total pressure of the system. (A) Decreases (B) Increases (C) Remains unchanged (D) May increase or decrease, depends on the system
Description : When an unsaturated air-water mixture is heated at constant pressure, then (A) The partial pressure of water vapour increases (B) The specific humidity decreases (C) The relative humidity increases (D) The relative humidity decreases
Last Answer : D) The relative humidity decreases
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 : For an ideal gas mixture undergoing a reversible gaseous phase chemical reaction, the equilibrium constant (A) Is independent of pressure (B) Increases with pressure (C) Decreases with pressure (D) Increases /decreases with pressure depending on the stoichiometric coefficients of the reaction
Last Answer : (B) Increases with pressure
Description : With increase in absolute humidity, the dew point of an unsaturated mixture of air and water vapor (at constant pressure and temperature). (A) Increases (B) Remains unchanged (C) Decreases (D) Decreases linearly
Last Answer : (A) Increases
Description : Fugacity of a component in an ideal gas mixture is equal to the partial pressure of that component in the mixture. The fugacity of each component in a stable homogeneous solution at constant pressure and ... increases. (A) Decreases (B) Decreases exponentially (C) Increases (D) Remain constant
Last Answer : (C) Increases
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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : Dew point of a gas-vapour mixture (A) Increases with temperature rise (B) Decreases with temperature rise (C) Decreases with decrease in pressure (D) Increases with increase in pressure
Last Answer : (C) Decreases with decrease in pressure
Description : Internal energy of an ideal gas (A) Increases with increase in pressure (B) Decreases with increase in temperature (C) Is independent of temperature (D) None of these
Last Answer : D) None of these
Description : On a day when the partial pressure of water vapor remains constant, what happens as the temperature rises? a. the relative humidity increases b. the relative humidity decreases c. the relative humidity remains constant d. the air would eventually become saturated
Last Answer : the relative humidity decreases
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 : Dew point of an air-water vapor mixture (A) Decreases with decrease in pressure (B) At constant humidity & total pressure is fixed (C) Corresponding to any point on the humidity chart is obtained by projecting a ... to the temperature axis and to the saturation curve (D) All 'a', 'b' & 'c'
Last Answer : (D) All 'a', 'b' & 'c'
Description : The relative saturation of a partially saturated mixture of vapour and gas can be increased by __________ of the mixture. (A) Reducing the total pressure (B) Increasing the total pressure (C) Reducing the temperature (D) Both (B) and (C)
Last Answer : (D) Both (B) and (C)
Description : When the __________ the relative humidity of air decreases, despite an increase in the absolute humidity. (A) Temperature rises (B) Pressure rises (C) Temperature falls (D) Pressure falls
Last Answer : (A) Temperature rises
Description : The absorptivity of a grey body at a given temperature __________ with increasing wavelength of radiation. (A) Increases (B) Decreases (C) Remain constant (D) May increase or decrease; depends on the material
Last Answer : (D) May increase or decrease; depends on the material
Description : The amount of chemical coagulant added for treatment of polluted water __________ with increase in temperature of the polluted water to be treated. (A) Decreases (B) Increases (C) Remain constant (D) May increase or decrease; depends on the chemical characteristics of polluted water
Last Answer : (A) Decreases
Description : With increase in temperature, the vapor pressure of liquids (A) Increases (B) Increases linearly (C) Decreases (D) Remain constant
Description : With increase in temperature, the equilibrium constant at constant pressure (Kp) for oxidation of sulphur dioxide (A) Increases (B) Increases linearly (C) Decreases (D) Decreases linearly
Last Answer : (C) Decreases
Description : Free energy, fugacity and activity co-efficient are all affected by change in the temperature. The fugacity co-efficient of a gas at constant pressure ____with the increase of reduced temperature. (A) Decreases (B) Increases (C) Remains constant
Description : With increase in reduced temperature, the fugacity co-efficient of a gas at constant reduced pressure (A) Increases (B) Decreases (C) Remain same (D) Decreases linearly
Description : If helium is introduced in a reactor containing O2 , SO2 and SO3 at equilibrium, so that total pressure increases while volume and temperature remains constant. In this case the dissociation of SO3 ( ... 's principle). (A) Decreases (B) Increases (C) Remains unaltered (D) Changes unpredictably
Description : During electrical desalting of crude oil, the electrical conductivity of a mixture of crude oil and water (which ranges between 3 to 8% water) __________ with increase in the amount of water. (A) Decreases (B) Increases (C) Remains unchanged (D) Decreases linearly
Description : Molecular diffusivity of a liquid (A) Increases with temperature (B) Decreases with temperature (C) May increase or decrease with temperature (D) Is independent of temperature
Last Answer : (A) Increases with temperature
Description : If the temperature of a piece increases suddenly, the relative humidity– (1) increases (2) decreases (3) remains constant (4) fluctuates
Last Answer : (2) decreases Explanation: Relative humidity is the ratio of the partial pressure of water vapour in a airwater mixture to the saturated vapour pressure of water at a specific temperature.
Description : If the temperature of a place increases suddenly, the relative humidity – (1) Increases (2) Decreases (3) Remains constant (4) Fluctuates
Last Answer : (2) Decreases Explanation: Relative humidity is the ratio of the partial pressure of water vapor in an airwater mixture to the saturated vapor pressure of water at a prescribed ... of the system decreases because the saturated vapor pressure of water increases with increasing temperature.
Description : If the temperature of a place increases suddenly, the relative humidity (1) Increases (2) Decreases (3) Remains constant (4) Fluctuates
Last Answer : Decreases
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
Description : At a given temperature, the volume of a gas dissolved in a solvent __________ with increase in pressure. (A) Increases (B) Decreases (C) Remains unchanged (D) May increase or decrease; depends on the gas
Last Answer : C) Remains unchanged
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