Pick out the wrong statement. Generally for physical adsorption, a gas

of

(A) Higher molecular weight is adsorbed in preference to a gas of low

molecular weight

(B) High critical temperature is adsorbed in preference to a gas of low

critical temperature

(C) Low volatility is adsorbed in preference to a gas of high volatility

(D) None of these


1 Answer

Answer :

(D) None of these


Related questions

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 : The change in enthalpy per unit weight of adsorbed gas when adsorbed on gas free or "outgassed" adsorbent to from a definite concentration of adsorbate is called its (A) Integral heat of adsorption (B) Heat of wetting (C) Differential heat of adsorption (D) Heat of normal condensation

Last Answer : (A) Integral heat of adsorption

Description : Assertion(A): Physical adsorption of molecules on the surface requires activation energy. Reason(R): Because the bonds of adsorbed molecules are broke

Last Answer : Assertion(A): Physical adsorption of molecules on the surface requires activation energy. Reason(R): ... D. If both Assertion & Reason are False.

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

Description : The change in enthalpy, when a unit quantity of gas is absorbed by relatively large quantity of adsorbent (on which a definite concentration of the adsorbed gas already exists) is termed as the (A) ... (B) Heat of wetting (C) Integral heat of adsorption (D) None of these

Last Answer : (A) Differential heat of adsorption

Description : An adsorption isotherm equation proposed by Langmuir is of the form `V = (V_(0)bPO)/((1 + bP))` where V is the volume of gas adsorbed at pressure P. F

Last Answer : An adsorption isotherm equation proposed by Langmuir is of the form `V = (V_(0)bPO)/((1 + bP))` where V is ... of V on P can be depicted as B. C. D.

Description : Adsorption of a gas follows Freundlich adsorption isotherm. In the given plot, x is the mass of the gas adsorbed on mass m of the adsorbent at pressur

Last Answer : Adsorption of a gas follows Freundlich adsorption isotherm. In the given plot, x is the mass of the gas adsorbed on mass m ... p^(1//2)` D. `p^(1//4)`

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 : Which of the following assumptions of Freunlich adsorption isotherm is incorrect? (a) The constants are temperature dependent (b) It is valid over a range of pressure only (c) Adsorption ... equation is purely an empirical equation (d) The adsorbed molecules may be multimolecular in thickness

Last Answer : (d) The adsorbed molecules may be multimolecular in thickness

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 : 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 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 : In Langmuir treatment of adsorption, (A) Whole surface of the catalyst does not have the same activity for adsorption and there is attraction between the adsorbed molecule (B) Whole surface of ... same mechanism (D) Extent of adsorption is more than one complete monomolecular layer on the surface

Last Answer : (B) Whole surface of the catalyst is essentially uniform and the adsorbed molecule has no effect on the rate of adsorption per site

Description : Brunauer, Emmet and Teller (BET) equation is used to determine the specific surface area of a porous particle but not the pore volume & the porosity of the catalyst bed. Which of the following postulates ... (except the first one) is involved in each of the evaporation process (D) None of these

Last Answer : (B) There is no dynamic equilibrium between successive layer

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 : 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

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 : Pick out the wrong statement. (A) Higher specific gravity of petroleum products means higher C/H ratio (B) Aromatics have lower specific gravity than corresponding paraffins (C) Hydrocarbons of low ... of high specific gravity (e.g., aromatics) possess the maximum thermal energy per unit weight

Last Answer : (B) Aromatics have lower specific gravity than corresponding paraffins

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

Description : Pick out the wrong statement. (A) Pulverised fuel can be completely burnt with less percentage of excess air compared to lump coal (B) Low grade coal can be used, but generally high volatile ... and atmosphere (oxidising or reducing) is easily possible with pulverised fuel firing (D) None of these

Last Answer : (D) None of these

Description : Pick out the wrong statement. (A) Mechanical agitation is required, if the system has low interfacial tension (B) Sieve tray towers are generally used for systems having low ... Prandtl analogy for heat and mass transfer considers the transfer through both laminar and turbulent layers

Last Answer : (A) Mechanical agitation is required, if the system has low interfacial tension

Description : Pick the wrong statement: hydrogen bonding results in (a) Increased solubility in water (b) Higher Van der Waal's forces (c) Molecular association (d) Abnormal boiling point

Last Answer : Ans:(b)

Description : Pick out the wrong statement. (A) A ferromagnetic material becomes paramagnetic above the 'Curie temperature' (B) Permanent magnets are made of hard materials, whereas electromagnets require soft ... hysterisis loss and coercive forces (D) Tungsten steel and alnico are not hard magnetic materials

Last Answer : Option D

Description : Pick out the wrong statement about the smoking tendency of various hydrocarbon constituents of kerosene. (A) Smoking tendency of hydrocarbons increases in the order: paraffins → isoparaffins → naphthenes → aromatics (B) Smoking tendency of paraffins increases with decrease in its molecular weight

Last Answer : (B) Smoking tendency of paraffins increases with decrease in its molecular weight

Description : Pick out the wrong statement pertaining to the properties of glasses. Glasses generally have (A) High electrical insulation properties (B) Sharp melting points (C) Low co-efficient of thermal expansion (D) Compressive strength much greater than their tensile strengths

Last Answer : (B) Sharp melting points

Description : Pick out the wrong statement. (A) In a multistep reaction, the slowest step is the rate determining step (B) In general, the rate of a reaction becomes triple for every 10°C rise in temperature (C ... energy (D) Molecularity of a reaction cannot be zero but the order of a reaction can be zero

Last Answer : (B) In general, the rate of a reaction becomes triple for every 10°C rise in temperature

Description : Pick out the wrong statement. (A) Alkylation produces a larger iso-paraffin (having higher octane number) from the reaction of an olefin with smaller iso-paraffin (B) Catalytic alkylation processes use HF ... (> 1000°C) (D) Gasoline having an octane number of 90 can be produced by alkylation process

Last Answer : (C) All the alkylation processes use very high temperature (> 1000°C)

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

Last Answer : (B) Decreases

Description : Pick out the correct statement. (A) Diffusivity decreases with increase in temperature (B) Diffusivity increases with increase in molecular weight (C) Diffusivity increases with the size of the individual molecule (D) None of these

Last Answer : (D) None of these

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 correct statement. (A) Angle of repose is always greater than the angle of slide (B) A hopper is a small bin with a sloping bottom (C) A silo is a short height ... used as a 'modifying agent' (for activating or depressing the adsorption of filming agents) in froth floatation process

Last Answer : (B) A hopper is a small bin with a sloping bottom

Description : Pick out the wrong statement. (A) Aromatics have higher specific gravity than paraffins (B) Gross calorific value (GCV) of petrofuels is equal to (12400 - 2100 ρ 2 ) where, ρ is the specific gravity ... volume basis (i.e., Kcal/litre) (D) Higher specific gravity of petrofuels means higher C/H ratio

Last Answer : (C) Heavier petrofuels have higher GCV on weight basis (i.e., Kcal/kg) but lower GCV on volume basis (i.e., Kcal/litre)

Description : Pick out the wrong statement. (A) Higher temperature is employed in visbreaking than in thermal cracking (B) Pyrolysis is a mild thermal cracking process (C) Lead susceptibility of ... Operating pressure and temperature in thermal cracking process is more than that in catalytic cracking process

Last Answer : (A) Higher temperature is employed in visbreaking than in thermal cracking (B) Pyrolysis is a mild thermal cracking process

Description : Pick out the wrong statement. (A) Biological oxygen demand (B.O.D.) value of a sewerage sample is always lower than its chemical oxygen demand (C.O.D.) value (B) Environmental pollution by ... in but does not allow the short wavelength infra red radiation to escape out of the earth's atmosphere

Last Answer : (D) The characteristic of a green house body is that it allows the long wavelength incoming solar radiation to come in but does not allow the short wavelength infra red radiation to escape out of the earth's atmosphere

Description : Pick out the wrong statement. (A) Exit age description function (E) and internal age distribution function (I) are related as, E = -(dI/dθ) (B) Chemisorption studies are useful in the ... energy (D) A catalyst increases the potential energy barrier over which the reactants must pass to form products

Last Answer : (D) A catalyst increases the potential energy barrier over which the reactants must pass to form products

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

Description : Pick out the wrong statement. Raoult's law does not apply, when the (A) Size of component molecules are not equal (B) Attractive forces between like and unlike molecules ... D) Chemical combination or molecular association between unlike molecules takes place in the formation of solution

Last Answer : (C) Component molecules are non-polar

Description : Hydrogen is recovered from coke oven gas on commercial scale (as practised in fertiliser plant at Rourkela) by (A) Adsorption on palladium (B) Cryogenic operations (low temperature cooling) (C) Absorption (using ethanolamine or pyrogallol solution) (D) None of these

Last Answer : (B) Cryogenic operations (low temperature cooling)

Description : . Pick out the wrong statement. (A) Multigrade lubricating oils have high viscosity index (B) Paraffinic oil has very high viscosity index (C) Naphthenic oil has very low viscosity index (D) High viscosity index means a large change in viscosity with change in temperature

Last Answer : (D) High viscosity index means a large change in viscosity with change in temperature

Description : Pick out the wrong statement. (A) A particular chemical reaction is more temperature sensitive at low temperatures (B) A very high value of equilibrium constant, K (K >> 1) indicates that the ... ) Non-ideal flow takes place in reactors due to recycling, channeling or by creation of stagnant regions

Last Answer : (C) The intercept of the Arrhenius plot is called the 'activation energy

Description : Pick out the wrong statement. (A) Weldability of high carbon steel is poorer compared to low carbon steel (B) Invar is a magnetic alloy (C) Magnetic permeability of the diamagnetic material is less than one (D) Martenistic transformation never goes to completion (i.e., 100%) at room temperature

Last Answer : Option B

Description : Adsorption is a unit operation which generally involves __________ systems. (A) Liquid-solid (B) Gas-solid (C) Fluid-solid (D) Solid-solid

Last Answer : (C) Fluid-solid

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 : Pick out the wrong statement. (A) A soft magnetic material should have high permeability and small area of hysteresis loop (B) Poisson's ratio of high melting point metals is more than unity (C) ... less than 185°C (D) Steel produced by B.O.F process is ideally suited for manufacturing flat product

Last Answer : Option B

Description : The probability of knocking in diesel engines is increased by a. High self-ignition temperature. b. Low volatility. c. High viscosity. d. all of the above

Last Answer : ANSWER d. all of the above

Description : The probability of knocking in diesel engines is increased by a. High self-ignition temperature. b. Low volatility. c. High viscosity. d. All of the above

Last Answer : ANSWER d. all of the above

Description : Pick out the wrong statement. (A) A slight haze at the top of chimney indicates good combustion in the furnace (B) A bag filter incurs very small pressure drop and is very efficient for ... dust collection equipment for removal of submicronic dust particles present in flue gas (D) None of these

Last Answer : (B) A bag filter incurs very small pressure drop and is very efficient for removal of submicronic dust particles from flue gases at very high temperature

Description : Pick up the correct statement from the following: (A) The amount of water retained on the surface of soil grains by molecular attraction, is known as pellicular water (B) The degree of resistance to ... (C) The pellicular water held in any soil, is called field capacity (D) All the above

Last Answer : Answer: Option D

Description : At equilibrium the concentration of water in vapour phase (C* ) in kg/m3 of air space and the amount of water (m) adsorbed per kg of dry silica gel are related by, C* = 0.0667m. To maintain dry conditions in a room ... which the temperature is maintained constant) is (A) 0.0 (B) 0.2 (C) 0.4 (D) 1.0

Last Answer : (C) 0.4

Description : Choose the correct statement. (A) Coking tendency increases with increasing molecular weight (B) Coking tendency decreases with increasing molecular weight (C) Higher pressure enhances coke formation (D) Coking is an exothermic reaction

Last Answer : (A) Coking tendency increases with increasing molecular weigh