Description : With increase in temperature, the rate of leaching increases, because the (A) Diffusivity of solute increases (B) Viscosity of solvent decreases (C) Thermal conductivity of solute increases (D) None of these
Last Answer : (A) Diffusivity of solute increases
Description : With increase in temperature, the leaching rate increases because of the (A) Increased diffusivity (B) Decreased viscosity of liquid (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) and (B)
Description : With increase in temperature, the leaching rate increases due to (A) Decreased liquid viscosity (B) Increased diffusivity (C) Both (A) and (B) (D) Neither (A) nor (B)
Description : Pick out the wrong statement pertaining to solvent extraction of oil. Rate of extraction (A) Decreases with decrease of thickness of the flakes (B) Increases with the increasing flake size ... considerably with the rise of temperature (D) Decreases as the moisture content of flakes increases
Last Answer : (D) Decreases as the moisture content of flakes increases
Description : Pick out the wrong statement: (A) Change in barometric pressure does not affect the relative humidity (B) In case of a packed tower, the operating velocity is about half of the ... (D) The equilibrium moisture content of the solid can be reduced by increasing the absolute humidity
Last Answer : (D) The equilibrium moisture content of the solid can be reduced by increasing the absolute humidity
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
Description : With increase in temperature, the rate of extraction in leaching (solidliquid extraction system). (A) Increases (B) Decreases (C) Remain unaffected (D) Increases Linearly
Last Answer : (A) Increases
Description : The film co-efficient between condensing vapour and metal wall increases with (A) Increasing temperature of the vapour (B) Decreasing temperature of the vapour (C) Increasing viscosity of the film of condensate (D) Increasing temperature drop
Last Answer : (A) Increasing temperature of the vapour
Description : Which of the following is the most commonly used leaching solvent in vegetable oil industry? (A) Phenol (B) Hexane
Last Answer : (B) Hexane
Description : Degree of freedom for leaching and solvent extraction process is (A) 0 (B) 1 (C) 2 (D) 3
Last Answer : (D) 3
Description : Separation of the isotopes of helium for scientific investigations is done by (A) Reverse osmosis (B) Thermal diffusion (C) Leaching (D) Solvent extraction
Last Answer : (B) Thermal diffusion
Description : Essential oils are usually obtained using (A) Steam distillation (B) Extractive distillation (C) Solvent extraction (D) Leaching
Last Answer : (D) Leaching
Description : The leaching solvent used in Baeyer's process for the purification of bauxite is (A) Ammonium hydroxide (B) Sodium carbonate (C) Sodium hydroxide (D) Ammonium carbonate
Last Answer : Option B
Description : Leaching rate is independent of the (A) Agitation (B) Temperature (C) Particle size (D) None of these
Last Answer : (D) None of these
Description : A good solvent used for absorption should not have very high (A) Viscosity (B) Vapor pressure (C) Freezing point (D) All (A), (B) & (C)
Last Answer : (D) All (A), (B) & (C)
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
Description : The rate constant of a chemical reaction increases by increasing the (A) Temperature (B) Pressure (C) Reactant's concentration (D) None of these
Last Answer : (A) Temperature
Description : During the manufacture of sulphuric acid, the temperature of molten sulphur is not increased beyond 160°C, as (A) It is very corrosive at elevated temperature (B) Its viscosity is not reduced on ... be further reduced) (C) It decomposes on further increasing the temperature (D) None of these
Last Answer : (B) Its viscosity is not reduced on further heating (hence pressure drop on pumping it, cannot be further reduced)
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 : 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 : Which of the following is the most controlling factor for the rate of bubble detachment from the hot solid surface? (A) Liquid density (B) Liquid viscosity (C) Hot surface temperature (D) Interfacial tension
Last Answer : (D) Interfacial tension
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'
Description : Pick out the wrong statement. (A) In drying a solid containing moisture above the critical moisture content the number of degrees of freedom is 2 (B) Sherwood number in mass transfer corresponds to ... tube heat exchangers. At higher pressure, however, it is customary to put gas in the tube side
Last Answer : (C) Forced convection is relatively more effective in increasing the rate of mass transfer, if Schmidt number is larger
Description : During the constant rate period of drying of a solid, (A) Increased air humidity decreases the rate of drying (B) Increasing the air temperature decreases the drying rate (C) Surface evaporation of unbound moisture occurs (D) None of these
Last Answer : (C) Surface evaporation of unbound moisture occurs
Description : Leaching of coarse solid lumps is also termed as (A) Decoction (B) Dissolution (C) Percolation (D) Agitation and settling
Last Answer : (C) Percolation
Description : With increase in gas rate, the number of transfer units, NtoG, for a fixed degree of absorption by a fixed amount of solvent (A) Increases (B) Decreases (C) Decreases linearly (D) Remains unaffected
Description : With increase in solvent rate, the number of transfer units, NtoG, for a fixed degree of absorption from a fixed amount of gas (A) Increases (B) Decreases (C) Decreases linearly (D) Remain unaffected
Last Answer : (B) Decreases
Description : Pick out the wrong statement regarding the solubility characteristics of high polymers. (A) Greater the degree of cross-linking in the polymer, lesser is its solubility (B) Polymers having more ... of the solvent (D) High molecular weight polymers on dissolving gives solution of very low viscosity
Last Answer : (D) High molecular weight polymers on dissolving gives solution of very low viscosity
Description : __________ treatment is done for appreciable improvement in viscosity index of lubricating oil. (A) Acid (B) Solvent extraction (C) Alkali (D) Clay
Last Answer : (B) Solvent extraction
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 extraction is the terminology applied to the liquid-liquid extraction, which is preferred for the separation of the components of liquids, when (A) Extracting solvent is cheaply & abundantly available ... very high (D) One of the liquid components has very high affinity towards the solvent
Last Answer : (D) One of the liquid components has very high affinity towards the solvent
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 terminal velocity of a solid spherical particle falling through a stationary fluid mass in the Stoke's law range is proportional to the (A) Inverse of fluid viscosity (B) Square of particle size (C) Difference in the densities of the particle & fluid (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : Pick out the correct statement. (A) Higher is the temperature of the radiating body, higher is the wavelength of radiation (B) Logarithmic mean area is used for calculating the heat flow rate ... ) Solid angle subtended by the finite surface at the radiating element is called the angle of incidence
Last Answer : (B) Logarithmic mean area is used for calculating the heat flow rate through a thick walled cylinder
Description : Pick out the wrong statement. (A) Bubble size increases with the dynamic viscosity of the liquid in case of nucleate pool boiling (B) Thermal conductivity of a dry material is more than ... in kg/hr in an evaporator (D) Vaporisation of organic substances in evaporator mostly causes foam formation
Last Answer : (B) Thermal conductivity of a dry material is more than that of the damp material
Description : A fluid whose apparent viscosity increases with shear rate is termed as the __________ fluid. (A) Newtonian (B) Viscous (C) Dilatant (D) Non-viscous
Last Answer : (C) Dilatan
Description : With increase in the shear rate, the apparent viscosity of pseudo-plastic fluids (A) Increases (B) Decreases (C) Remain same (D) May increase or decrease; depends on the magnitude of shear rate
Description : At a given equilibrium pressure, with increase in temperature, the concentration of adsorbed gas on solid adsorbent (A) Increases (B) Decreases (C) Remains unchanged (D) Increases exponentially
Description : The settlement of a particle in sedimentation tank, is affected by A. Velocity of flow B. Viscosity of water C. Size and shape of solid D. All the above
Last Answer : ANS: D
Description : Explain the effect of increasing the temperature of a liquid, on intermolecular forces operating between its particles. What will happen to the viscosity of a liquid if its temperature is increased? Arrange the following in increasing order of viscosity-water, hexane, glycerine.
Last Answer : Ans. On increasing the temperature , the kinetic energy of liquid molecules increases so that it can overcome the attractive forces between the molecules and hence liquid can flow more easily i.e. viscosity decreases. Order of increasing viscosity : hexane < water < glycerine.
Description : The falling rate period in the drying of a solid is characterised by (A) Increase in rate of drying (B) Increasing temperatures both on the surface and within the solid (C) Decreasing temperatures (D) None of these
Last Answer : (B) Increasing temperatures both on the surface and within the solid
Description : For water, when the pressure increases, the viscosity (A) Also increases (B) Decreases (C) Remain constant (D) First decreases, and then increases
Last Answer : (D) First decreases, and then increases
Description : When the water is warm, the height to which it can be lifted by a pump (A) Decreases due to reduced viscosity (B) Decreases due to reduced vapour pressure (C) Increases due to increased vapour pressure (D) Decreases due to increased frictional resistance
Last Answer : (B) Decreases due to reduced vapour pressure
Description : Pick out the wrong statement. (A) Cellulose acetate membranes are used in dialysis process (B) Elutriation process refers to when the soluble material is largely concentrated on the surface of an ... that various streamflow from one to another (D) Zirconia probe is used for the humidity measurement
Last Answer : (D) Zirconia probe is used for the humidity measurement
Description : The operation involved when the soluble material is largely on the surface of an insoluble solid and is merely washed off by the solvent is called (A) Decoction (B) Percolation (C) Elutriation or elution (D) None of these
Last Answer : (C) Elutriation or elution
Description : Viscosity of a polymer solution or melt (A) Decreases with increase in molecular weight (B) Decreases with increase in temperature (C) Increases with increase in temperature (D) Does not vary with temperature rise
Last Answer : (C) Increases with increase in temperature
Description : With increase in the temperature, viscosity of a liquid (A) Increases (B) Decreases (C) Remain constant (D) May increase or decrease; depends on the liquid
Description : . Pick out the wrong statement. (A) The eddy viscosity is a function of the type of turbulence involved (B) The eddy viscosity is a fluid property (C) The viscosity of gas increases with increase in temperature (D) The viscosity of a liquid increases with decrease in temperature
Last Answer : (B) The eddy viscosity is a fluid property
Description : Why are there jets in the midlatitudes in the upper troposphere? (a) Air is warmer in the tropics than the poles, resulting in a poleward pressure gradient that increases with increasing height. (b) Because ... d) Due to the constant bending by the Coriolis force. (e) Both A and D are correct.
Last Answer : (e) Both A and D are correct.
Description : In case of grinding in a ball mill (A) Wet grinding achieves a finer product size than dry grinding (B) Its capacity decreases with increasing fineness of the products (C) Grinding cost and power requirement increases with increasing fineness of the products (D) All (A), (B) and (C)