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

(C) Particles movement from higher concentration to lower concentration

takes place in diffusion process

(D) According to Poiseuille's law, the permeability decreases with increase in

temperature for flow of a gas through a given capillary

1 Answer

Answer :

(B) Molecular diffusion in solid is much faster than that in liquids

Related questions

Description : According to Poiseuille's law, the permeability for gas flow through a capillary is proportional to (where, μ = gas viscosity) (A) μ (B) 1/μ (C) √μ (D) μ

Last Answer : (B) 1/μ

Description : Pick out the wrong statement. (A) The Reynolds analogy for mass transfer is given by Lewis relation and is applicable, when Schmidt number is one (B) Sherwood number for flow in pipes can be expressed ... flux of a component A in binary mixture of A and B is given by - Dab'.dCA/dz

Last Answer : (C) According to film theory for equimolar counter diffusion, the mass transfer coefficient is given by DAB(B)P - 3, Q - 2

Description : For the flow of gases through a capillary, with increase in temperature, the permeability __________ as per Knudsen law. (A) Increases (B) Decreases (C) Remain same (D) Either (A) or (B); depends on the gas

Last Answer : (A) Increases

Description : Pick out the wrong statement. (A) A fluid mass is free from shearing forces, when it is made to rotate with a uniform velocit (B) Newton's law of viscosity is not applicable to the ... types of bearings (D) Rise of water in capillary tubes reduces with the increasing diameter of capillary tubes

Last Answer : (B) Newton's law of viscosity is not applicable to the turbulent flow of fluid with linear velocity distribution

Description : The binary diffusivity in gases at atmospheric conditions is about (A) 10 -9 cm/sec (B) 10 -1 cm2 /sec (C) 10 -3 sec/cm (D) 10 -4 cm2 /sec

Last Answer : (B) 10 -1 cm2 /sec

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 liquid-liquid binary diffusion, diffusivity of one constituent into another is not dependent on the (A) Temperature and pressure (B) Concentration (C) Nature of the constituents (D) None of these

Last Answer : (D) None of these

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 : 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 : A fountain pen works on the principle of (1) Flow of liquids from higher to lower potential (2) Capillary action (3) Bernoulli's principle (4) Viscosity of liquids

Last Answer : (2) Capillary action Explanation: A fountain pen is a nib pen that, unlike its predecessor the dip pen, contains an internal reservoir of water-based liquid ink. The pen draws ink from the ... to flow in narrow spaces without the assistance of, and in opposition to external forces like gravity.

Description : A fountain pen works on the principle of (1) flow of liquids from higher to lower potential (2) capillary action (3) Bernoulli’s principle (4) Viscosity of liquids

Last Answer : capillary action

Description : Capillary tube method of viscosity measurement is based on the (A) Hagen-Poiseuille’s equation (B) Stoke's law (C) Navier-stokes equation (D) None of these

Last Answer : (A) Hagen-Poiseuille’s equation

Description : In case of liquids, the binary diffusivity is proportional to (where, T = temperature) (A) T (B) √T (C) T 2 (D) 1/T

Last Answer : (A) T

Description : Pick out the wrong statement. (A) In the McCabe-Thiele diagram for binary distillation, vertical feed line represents saturated liquid feed and horizontal feed line represents saturated vapour feed (B) In ... layers over a flat plate are of equal thickness, if Schmidt number is equal to unity

Last Answer : (C) For Laminar flow over a plate of length L, the local mass transfer co￾efficient at a distance L from the leading edge is 1.5 × 10 -2m/s. Then the average mass transfer co-efficient for the plate is 2 × 10 -2m/s

Description : Pick out the wrong statement. (A) In a first order reaction, A → products; the reaction becomes slower as it proceeds, because the concentration of A decreases and the rate is proportional to the concentration ... irreversible reaction, A + B → 2C is k.CA .CB , then the reaction is always elementary

Last Answer : (C) According to the penetration theory, the mass transfer co-efficient decreases, if the exposure time of an eddy to the solute decreases

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 : 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 : Pick out the wrong statement. (A) In a static mass of liquid, the pressure at a point is the same for all liquids (B) Pressure decreases exponentially with elevation in an isothermal atmosphere (C) ... s law, the pressure at a point in a static or uniformly moving fluid is equal in all directions

Last Answer : (A) In a static mass of liquid, the pressure at a point is the same for all liquids

Description : Which of the following is not a dimension-less group used in catalysis? (Where, D = dispersion co-efficient, cm2 /sec.D1 = diffusion co-efficient; cm2 /sec L = length of the reactor, cm t = time, sec, v = volumetric ... (D/vL) (B) Reduced time (vt/V) (C) Thiele modulus L √(k/D1 ) (D) None of these

Last Answer : (D) None of these

Description : The unit of volumetric diffusivity is (A) cm2 /sec (B) cm/sec (C) cm3 /sec (D) cm2 /sec

Last Answer : (A) cm2 /sec

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 : The diffusivity, DAB (for component A diffusing in B) is equal to the diffusivity DBA (for component B diffusing in A) for a binary mixture of (A) Newtonian liquids (B) Non-Newtonian liquids (C) Ideal gases (D) Real gases

Last Answer : (C) Ideal gases

Description : 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 ... volatility is adsorbed in preference to a gas of high volatility (D) None of these

Last Answer : (D) None of these

Description : Pick out the wrong conversion of absolute & kinematic viscosities. (A) 1 stoke = 1 cm2/sec (B) 1 N.sec/m2 = 10 paise (C) 1 stoke = 1 m2/sec (D) 1 m2/sec = 104 stokes

Last Answer : (C) 1 stoke = 1 m2/sec

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. (A) An ideal liquid or solid solution is defined as one in which each component obeys Raoult's law (B) If Raoult's law is applied to one component of a binary mixture; ... also (C) Henry's law is rigorously correct in the limit of infinite dilution (D) None of these

Last Answer : (D) None of these

Description : Pick out the wrong statement. (A) Lead can creep under its own weight at room temperature (B) The electrical conductivity of gold is considerably reduced by alloying additions due to ... metal (D) With increase in temperature, the electrical conductivity of intrinsic semi-conductor will increase

Last Answer : (C) Recrystallisation temperature decreases with decrease in strain in a cold worked metal

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 : 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 : Liquid diffusivity is of the order of __________ cm2 /second. (A) 0.01 (B) 0.1 (C) 10 -5 to 10 -6 (D) > 1

Last Answer : (C) 10 -5 to 10

Description : Gaseous diffusivity at atmospheric pressure is of the order of __________ cm2 /second. (A) 1 (B) 1 to 5 (C) 5 to 10 (D) > 10

Last Answer : (A) 1

Description : Pick up the incorrect statement from the following: (A) Compaction has no effect on the structure of a soil (B) Permeability decreases with increase in the dry density of a compacted soil (C) ... a dry side compacted soil (D) Dry side compaction soils swell more when given access to moisture

Last Answer : (A) Compaction has no effect on the structure of a soil

Description : Pick out the wrong statement. (A) The condensing film co-efficient is about 3 times lower for vertical condenser as compared to the equivalent horizontal condenser for identical situation ( ... in a heat exchanger is controlled by the value of the film co-efficient, which is higher

Last Answer : (D) Overall heat transfer co-efficient in a heat exchanger is controlled by the value of the film co-efficient, which is higher

Description : The effectiveness factor for large value of Thiele modulus [L√(K/D1 )] of a solid catalysed first order reaction is equal to (where, L = length of the reactor, cm, D1 = diffusion co-efficient, cm2 /second). (A) L √(K/D1 ) (B) 1/[L√(K/D1 )] (C) 1 (D) ∞

Last Answer : (B) 1/[L√(K/D1 )]

Description : Pick out the wrong statement. (A) Fluid movement under the influence of buoyant forces resulting from change in density takes place in case of natural convection (B) The ratio NNu /NRe . Npr is ... convection to that by conduction (D) The Colburn jH factor for heat transfer is given by Nst Npr

Last Answer : (D) The Colburn jH factor for heat transfer is given by Nst Npr

Description : For gases, the thermal conductivity increases with temperature rise. For liquids, with increase in concentration, its thermal conductivity generally (A) Decreases (B) Increases (C) Remains unchanged (D) Increases exponentially

Last Answer : (A) Decreases

Description : The rough value of diffusion co-efficient of water vapor into air at 25°C may be about __________ cm2 /sec. (A) 0.25 (B) 2.5 (C) 1.25 (D) 0.0025

Last Answer : (A) 0.25

Description : Choose the wrong statement (A) Viscosity of a fluid is that property which determines the amount of its resistance to a shearing force (B) Viscosity is due primarily to interaction between fluid molecules (C) Viscosity of liquids decreases with increase in temperature (D) Viscosity of liquid

Last Answer : Answer: Option D

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 : Pick out the wrong statement. (A) Trouton's ratio of non-polar liquids is calculated using Kistyakowsky equation (B) Thermal efficiency of a Carnot engine is always less than 1 (C) An equation relating pressure, volume and temperature of a gas is called ideal gas equation (D) None of these

Last Answer : (C) An equation relating pressure, volume and temperature of a gas is called ideal gas equation

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) 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 : The coefficient of permeability of soils, is generally expressed in (A) cm/sec (B) cm/minute (C) cm2 /sec (D) cm2 /minute

Last Answer : (A) cm/sec

Description : The movement of particles or molecules  of a substance from the region of higher con- centration to a region of lower concentration  is called........ 

Last Answer : Diffusion

Description : Pick out the wrong statement about cavitation. (A) Sudden reduction of pressure in a fluid flow system caused by flow separation, vortex formation or abrupt closing of valve leads to cavitation ... (D) Large scale cavitation cannot damage pipeline, restrict fluid flow and damage steam turbine blades

Last Answer : (D) Large scale cavitation cannot damage pipeline, restrict fluid flow and damage steam turbine blades

Description : Pick out the wrong statement: (A) Greater is the kinematic viscosity of the liquid, greater is the thickness of the boundary layer (B) Blowers develop a maximum pressure of 2 atmospheres ( ... factor in case of turbulent flow of liquids in pipe depends upon relative roughness & Reynolds number

Last Answer : (C) Friction losses in pipe fittings are generally expressed in terms of velocity heads

Description : The diffusivity (D) in a binary gas mixture is related to the temperature (T) as (A) D ∝ T (B) D ∝ T 0.5 (C) D ∝ T 1.5 (D) D ∝ T

Last Answer : (C) D ∝ T 1.5

Description : Pick up the incorrect statement from the following: (A) The rate of flow of water through a unit cross-sectional area under a unit hydraulic gradient, is called coefficient of permeability (B) ... aquifers, is governed by the Darcy's law (D) The term 'transmissibility' was introduced by Meinzer

Last Answer : Answer: Option D