Absorption (liquid-gas system) with evolution of heat as compared to
isothermal absorption results in
(A) Decreased solute solubility
(B) Large minimum liquid to gas (L/G) ratio
(C) Large number of trays
(D) All (A), (B) and (C)
Description : Absorption accompanied by heat evolution results in (A) Increased capacity of the absorber (B) Increase in equilibrium solubility (C) Decrease in equilibrium solubility (D) None of these
Last Answer : (C) Decrease in equilibrium solubility
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 : Minimum reflux ratio in a distillation column results in (A) Optimum number of trays (B) Minimum reboiler size (C) Maximum condenser size (D) Minimum number of trays
Last Answer : (C) Maximum condenser size
Description : In an interphase mass transfer process, the lesser the solubility of a given solute in a liquid, the higher are the chances that the transfer process will be (A) Liquid phase resistance-controlled (B) Gas phase resistance controlled (C) Impossible (D) Driven by a non-linear driving forc
Last Answer : (B) Gas phase resistance controlled
Description : An aqueous solution of methanol is to be distilled in a tray column. High pressure steam is available as a source of heat. For a given reflux ratio and overhead composition, two options are ... (D) More number of trays are required and the residue composition is more dilute in methano
Last Answer : (A) Less number of trays are required
Description : When a multistage tray tower uses a minimum reflux ratio, it implies (A) Infinite trays and maximum reboiler heat load (B) Infinite trays and minimum reboiler heat load (C) Minimum trays and minimum reboiler heat load (D) Minimum trays and maximum reboiler heat load
Last Answer : (A) Infinite trays and maximum reboiler heat load
Description : Acetone is to be removed from air in an isothermal dilute absorber using pure water as solvent. The incoming air contains 5 mole% of acetone (yin = 0.05). The design equation to be used for obtaining the number of trays ( ... of acetone, the number of trays required is/are: (A) 4 (B) 8 (C) 9 (D) 10
Last Answer : (C) 9
Description : The individual mass transfer co-efficients (moles/m2s) for absorption of a solute from a gas mixture into a liquid solvent are, KL = 4.5 and KG = 1.5. The slope of the equilibrium line is 3. Which of ... A) Liquid side (B) Gas side (C) Interfacial (D) Both liquid and gas side
Last Answer : (B) Gas side
Description : . The absorption factor is defined as (where, L = liquid flow rate, G = gas flow rate and, m = slope of the equilibrium line). (A) L/mG (B) G/mL (C) mL/G (D) LG/m
Last Answer : (A) L/mG
Description : A negative heat of solution indicates that: w) an endothermic dissolving process occurs x) solute solubility increases with rising solution temperature y) solute solubility decreases with rising solution temperature z) super-saturation conditions exist
Last Answer : ANSWER: Y -- SOLUTE SOLUBILITY DECREASES WITH RISING SOLUTION TEMPERATURE
Description : Priming in a distillation column (A) Results from very low gas velocity (B) Is desirable from point efficiency consideration (C) Is characterised by the presence of foam throughout the space between trays (D) Reduces the overall pressure drop
Last Answer : (C) Is characterised by the presence of foam throughout the space between trays
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 : Pick out the wrong statement: (A) Absorption factor is constant, when the equilibrium and operating lines are straight (B) In case of a stripper, the equilibrium curve is always below ... (D) In the absorption of low solubility gases, the liquid film is the controlling resistance
Last Answer : (B) In case of a stripper, the equilibrium curve is always below the operating line
Description : Second order consecutive irreversible reaction as shown in the bellow figure, were carried out in a constant volume isothermal batch reactor with different initial feed compositions. Reactor temperature was same in all the cases. In experiments ... constants (k1 /k2 )? (A) 1/4 (B) 1/2 (C) 2 (D) 4
Last Answer : (A) 1/4
Description : Pick out the wrong statement. (A) When the concentration difference for the mass transfer becomes zero at the bottom of the gas absorption tower, then the upper end of the operating line touches the ... fixed gas flow rate, the slope of the operating line decreases, in case of gas absorption process
Last Answer : (C) The operating line lies above the equilibrium curve in case of a gas desorber
Description : If the heat of solution of an ideal gas in a liquid is negative, then its solubility at a given partial pressure varies with the temperature as (A) Solubility increases as temperature ... (D) Solubility increases or decreases with temperature depending on the Gibbs free energy change of solution
Last Answer : (B) Solubility increases as temperature decreases
Description : For absorbers, high pressure drop results in (A) Increased efficiency (B) Decreased efficiency (C) High operating cost (D) Better gas liquid contact
Last Answer : (C) High operating cost
Description : Which of the following is an undesirable characteristic for the solvent used in gas absorption? (A) Low vapor pressure (B) Low viscosity (C) High gas solubility (D) None of these
Last Answer : (D) None of these
Description : A multiple effect evaporator as compared to a single effect evaporator of the same capacity has (A) Lower heat transfer area (B) Lower steam economy (C) Higher steam economy (D) Higher solute concentration in the product
Last Answer : (C) Higher steam economy
Description : What is meant by solubility of a solute? -Chemistry 9th
Last Answer : Solubility is the relative ability of a solute to dissolve into a solvent. Several factors affect the solubility of a given solute in a given solvent. Temperature often plays the largest role, although pressure can have a significant effect for gases.
Description : A sharp moving boundary is obtained between the pure solvent and solute containing layer in (A) Chromatography (B) Immuno Reactivity (C) Ultra Centrifugation (D) Solubility curve
Last Answer : Answer :C
Description : Which action best accounts for the solubility of aldehydes and ketones in water? (a) Polar interactions between solute molecules. (b) H-bonding between solute molecules. (c) Van der waals forces (d) H-bonding between solute and solvent molecules
Last Answer : H-bonding between solute and solvent molecules
Description : Define the following : Solute , Solvent , Solution , Aqueous Solution & Solubility.
Last Answer : Ans : Solute : The component of the solution present in smaller amount is called solute. It is also defined as the substance that gets dissolved in the solvent. Example : Glucose is solute in glucose solution. ... grams / 100 grams. Solubility of sugar in water at 100 degree C is 487 grams/100 ml.
Description : Define solubility and give the effect of temperature on a solubility of solute.
Last Answer : Solubility: Solubility of a solute is the maximum amount of solute that can be dissolved in a given amount of solvent at a specific temperature and pressure. OR It is the amount of ... in gm/ litre of solution. Effect of temperature on solubility: Solubility increases as temperature increases.
Description : For a cold dilute feed to produce thick viscous liquor, backward feeding as compared to forward feeding results in (A) Increased economy (B) Decreased economy (C) Lower capacity (D) No effect on economy
Last Answer : (A) Increased economy
Description : For hot feed, forward feeding as compared to backward feeding results in __________ economy. (A) Increased (B) Decreased (C) No effect on (D) None of these
Last Answer : (A) Increased
Description : The mass transfer co-efficient for a solid sphere of radius 'a' dissolving in a large volume of quiescent liquid, in which ‘D’ is the diffusivity of solute, is (A) D/a (B) D/2a (C) Proportional to √D (D) Dependent on the Reynolds number
Last Answer : (D) Dependent on the Reynolds number
Description : On moving the feed line (q-line) from saturated liquid feed (vertical position) to saturated vapor feed (horizontal feed), if the slope of both the operating lines are to be increased, then it will result in (A) Greater degree of separation with a fixed number of trays (B) Increased reboiler load
Last Answer : (C) Increased reflux ratio
Description : The clearance volume of the air compressor is kept minimum because A. It allows maximum compression to be achieved B. It greatly affects volumetric efficiency C. It results in minimum work D. It permits isothermal compression
Last Answer : ANSWER : B
Description : Pick out the correct statement. (A) The available energy in an isolated system for all irreversible (real) processes decreases (B) The efficiency of a Carnot engine increases, if the sink temperature is decreased ... condition is the change in Helmholtz free energy (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
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 : During bottling of cold drinks (e.g. Pepsi), the main resistance to mass transfer for the absorption of carbon dioxide in water lies in the (A) Gas film (B) Liquid film (C) Liquid-gas interface
Last Answer : (B) Liquid film
Description : Physical absorption is (A) An irreversible phenomenon (B) A reversible phenomenon (C) Accompanied by evolution of heat (D) Both (B) and (C)
Last Answer : (D) Both (B) and (C)
Description : Pick out the correct statement. (A) A chemical reaction accompanied by absorption of heat is called an exothermic reaction (B) A chemical reaction accompanied by evolution of heat is called an ... does not change on changing the concentration units (D) Chemical equilibrium state is dynamic in nature
Last Answer : (C) The rate constant for a first order reaction does not change on changing the concentration units
Description : Absorption/evolution of heat during conversion of a substance from one allotropic form to another is termed as the heat of (A) Sublimation (B) Fusion (C) Transition (D) Vaporisation
Last Answer : C) Transition
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 : For nearly isothermal operation involving large reaction time in a liquid-phase reaction, the most suitable reactor is a __________ reactor. (A) Stirred tank (B) Tubular flow (C) Batch (D) Fixed bed
Last Answer : (A) Stirred tank
Description : Isothermal bulk modulus is equal to A. Υ × P; where Υ: the ratio of the specific heat capacities of the gas, P: pressure B. Pressure C. The ratio of the specific heat capacities of the gas D. Υ ⁄ P; where Υ: the ratio of the specific heat capacities of the gas, P: pressure
Last Answer : Pressure
Description : Hypolipidemic drugs reduce serum cholesterol and triacylglycerol. The effect of clofibrate is attributed to (A) Block in absorption from G.I.T. (B) Decrease in secretion of triacylglycerol and cholesterol ... by liver (C) Block in the reabsorption of bile acids (D) Decreased synthesis of cholesterol
Last Answer : Answer : B
Description : The Graetz number is concerned with the (A) Mass transfer between a gas and a liquid (B) Absorption with chemical reaction (C) Heat transfer in turbulent flow (D) Heat transfer in laminar flow
Last Answer : (D) Heat transfer in laminar flow
Description : When the solvent dissolves very little of solute, then (A) Solvent of low latent heat of vaporisation should be used (B) Solvent of low freezing point should be used (C) Large quantity of solvent is required to extract the solute (D) Very small quantity of solvent is required
Last Answer : (C) Large quantity of solvent is required to extract the solute
Description : Pick out the wrong statement. (A) At constant pressure, solubility of a gas in a liquid diminishes with rise in temperature (B) Normally, the gases which are easily liquefied are more soluble ... (D) At constant pressure, solubility of a gas in a liquid increases with rise in temperature
Last Answer : (A) At constant pressure, solubility of a gas in a liquid diminishes with rise in temperature
Description : Turn down ratio of a burner (A) Should be as low as possible i.e., 1 : 2 (B) Should be 1:1 for a batch type furnace (C) Is the ratio of maximum to minimum permissible heat input rates (D) Is normally much more for a continuous furnace as compared to a batch furnace
Last Answer : (C) Is the ratio of maximum to minimum permissible heat input rates
Description : An increase in the NH3 /CO2 ratio in urea manufacture results in (A) Increased degree of conversion of CO2 to urea (B) Decreased degree of conversion of NH3 to urea (C) Decreased yield of urea (D) Decreased specific volume of molten mass
Last Answer : (A) Increased degree of conversion of CO2 to urea
Description : In case of absorption, both the operating and equilibrium lines will be straight for (A) Isothermal operation (B) Dilute solutions (C) Dilute solutions and isothermal operation (D) None of these
Last Answer : (C) Dilute solutions and isothermal operation
Description : The evolution of heat of solution takes place in ammonia absorption plant when (a) ammonia vapour goes into solution (b) ammonia vapour is driven out of solution (c) lithium bromide mixes with ammonia (d) weak solution mixes with strong solution
Last Answer : Ans: a
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
Description : If G = insoluble gas in gas stream and L = non-volatile solvent in liquid stream, then the slope of the operating line for the absorber is (A) L/G (B) G/L (C) Always < 1 (D) None of these
Last Answer : (A) L/G
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 : Isothermal turbulent flow of a fluid results in decrease of its pressure, which depends on the (A) Wall roughness (B) Reynolds number (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) & (B)