Helium-mercury method can be used to determine the __________ of the catalyst particle. (A) Pore volume (B) Solid density (C) Porosity (D) All (A), (B), & (C)

Helium-mercury method can be used to determine the __________ of
the catalyst particle.
(A) Pore volume
(B) Solid density
(C) Porosity
(D) All (A), (B), & (C)
by

1 Answer

Answer :

(D) All (A), (B), & (C)
by

Related questions

Helium-mercury method is used for the measurement of the __________ of the catalyst. (A) Surface area (B) Porosity (C) Pore volume (D) Both (B) & (C)

Description : Helium-mercury method is used for the measurement of the __________ of the catalyst. (A) Surface area (B) Porosity (C) Pore volume (D) Both (B) & (C)

Last Answer : (D) Both (B) & (C)

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 is not used to derive BET equation? (A) Langmuir's assumption applies to every adsorbed layer (B) There is no dynamic equilibrium between successive layer (C) The adsorbed layer may be polymolecular in thickness and the heat of adsorption in each layer (except the first one) is involved in each of the evaporation process (D) None of these

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

. B.E.T. method can be used to determine the __________ of a porous catalyst. (A) Solid density (B) Pore volume (C) Surface area (D) All (A), (B) and (C)

Description : . B.E.T. method can be used to determine the __________ of a porous catalyst. (A) Solid density (B) Pore volume (C) Surface area (D) All (A), (B) and (C)

Last Answer : (C) Surface area

If pore diffusion is the controlling step in a solid catalysed reaction, the catalyst (A) Porosity is very important (B) Porosity is of less importance (C) Internal surface area is utilised efficiently (D) None of these

Description : If pore diffusion is the controlling step in a solid catalysed reaction, the catalyst (A) Porosity is very important (B) Porosity is of less importance (C) Internal surface area is utilised efficiently (D) None of these

Last Answer : (B) Porosity is of less importance

BET apparatus is used to determine the (A) Specific surface of a porous catalyst (B) Pore size distribution (C) Pore diameter (D) Porosity of the catalyst bed

Description : BET apparatus is used to determine the (A) Specific surface of a porous catalyst (B) Pore size distribution (C) Pore diameter (D) Porosity of the catalyst bed

Last Answer : (A) Specific surface of a porous catalyst

Pick out the correct statement. (A) A lower temperature favours the reaction of lower activation energy (B) The dispersion number for a reactor/vessel is uL/D (C) The rate controlling step in a reaction involving many steps is the fastest step (D) Pore volume and porosity of a catalyst is measured by Brunauer￾Emmett-Teller (BET) technique

Description : Pick out the correct statement. (A) A lower temperature favours the reaction of lower activation energy (B) The dispersion number for a reactor/vessel is uL/D (C) The rate controlling step in ... step (D) Pore volume and porosity of a catalyst is measured by Brunauer￾Emmett-Teller (BET) technique

Last Answer : (A) A lower temperature favours the reaction of lower activation energy

The importance of diffusion in a catalyst are increased by (A) Large catalyst particle size (B) An active surface of the catalyst (C) Small pore diameter (D) All (A), (B) and (C)

Description : The importance of diffusion in a catalyst are increased by (A) Large catalyst particle size (B) An active surface of the catalyst (C) Small pore diameter (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

In solid catalysed reactions the diffusional effects are more likely to affect the overall rate of reaction for (A) Fast reactions in catalyst of small pore diameter (B) Fast reaction in catalyst of large pore diameter (C) Slow reactions in catalyst of small pore diameter (D) Slow reactions in catalyst of large pore diameter

Description : In solid catalysed reactions the diffusional effects are more likely to affect the overall rate of reaction for (A) Fast reactions in catalyst of small pore diameter (B) Fast reaction in catalyst ... reactions in catalyst of small pore diameter (D) Slow reactions in catalyst of large pore diameter

Last Answer : (C) Slow reactions in catalyst of small pore diameter

If Thiele modulus is __________, then the pore diffusion resistance in a catalyst may be considered as negligible. (A) 0 (B) ∞ (C) < 0.5 (D) > 0.5

Description : If Thiele modulus is __________, then the pore diffusion resistance in a catalyst may be considered as negligible. (A) 0 (B) ∞ (C) < 0.5 (D) > 0.5

Last Answer : (C) < 0.5

Effectiveness factor of a catalyst pellet is a measure of the __________ resistance. (A) Pore diffusion (B) Gas film (C) Chemical reaction (D) None of these

Description : Effectiveness factor of a catalyst pellet is a measure of the __________ resistance. (A) Pore diffusion (B) Gas film (C) Chemical reaction (D) None of these

Last Answer : (A) Pore diffusion

Bulk diffusion in catalyst pore __________ with increase in pressure. (A) Increases (B) Decreases (C) Remains unchanged (D) Increases exponentially

Description : Bulk diffusion in catalyst pore __________ with increase in pressure. (A) Increases (B) Decreases (C) Remains unchanged (D) Increases exponentially

Last Answer : (B) Decreases

A gas (density = 1.5 kg/m3 , viscosity = 2 × 10 ‒5 kg/m.s) flowing through a packed bed (particle size = 0.5 cm, porosity = 0.5) at a superficial velocity of 2 m/s causes a pressure drop of 8400 Pa/m. The pressure drop for another gas, with density of 1.5 kg/m3and viscosity of 3 × 10 ‒5kg/m.s flowing at 3 m/s will be (A) 8400 Pa/m (B) 12600 Pa/m (C) 18900 Pa/m (D) 16800 Pa/m

Description : A gas (density = 1.5 kg/m3 , viscosity = 2 10 -5 kg/m.s) flowing through a packed bed (particle size = 0.5 cm, porosity = 0.5) at a superficial velocity of 2 m/s causes a pressure drop of 8400 Pa/m. The ... flowing at 3 m/s will be (A) 8400 Pa/m (B) 12600 Pa/m (C) 18900 Pa/m (D) 16800 Pa/m

Last Answer : (B) 12600 Pa/m

If the catalyst pore size is small in comparison with the mean free path, collisions with the pore wall controls the process'. The diffusivity under this condition is called 'Knudsen diffusivity', which is affected by the (A) Pressure (B) Temperature (C) Both (A) & (B) (D) Neither (A) nor (B)

Description : If the catalyst pore size is small in comparison with the mean free path, collisions with the pore wall controls the process'. The diffusivity under this condition is called 'Knudsen diffusivity', which is affected by the (A) Pressure (B) Temperature (C) Both (A) & (B) (D) Neither (A) nor (B)

Last Answer : (B) Temperature

Number of particles in a crushed solid sample is given by (where, m = mass of particles in a sample, Vp = volume of one particle, ρ= density of particles) (A) m/ρ . Vp (B) m . ρ/Vp (C) m . Vp /ρ (D) Vp /m . ρ

Description : Number of particles in a crushed solid sample is given by (where, m = mass of particles in a sample, Vp = volume of one particle, ρ= density of particles) (A) m/ρ . Vp (B) m . ρ/Vp (C) m . Vp /ρ (D) Vp /m . ρ

Last Answer : (A) m/ρ . Vp

Pick out the wrong statement. (A) The ratio of the density of the 'nucleus' to that of the 'atom' is 10 12 (B) α-particle is identical with a doubly charged helium ion (C) The mass of deuterium atom is half that of helium atom (D) Gamma rays are high energy electrons

Description : Pick out the wrong statement. (A) The ratio of the density of the 'nucleus' to that of the 'atom' is 10 12 (B) α-particle is identical with a doubly charged helium ion (C) The mass of deuterium atom is half that of helium atom (D) Gamma rays are high energy electrons

Last Answer : (D) Gamma rays are high energy electrons

The Knudsen diffusivity is dependent on the (A) Molecular velocity only (B) Pore radius of the catalyst only (C) Molecular mean free path only (D) Molecular velocity and pore radius of the catalyst

Description : The Knudsen diffusivity is dependent on the (A) Molecular velocity only (B) Pore radius of the catalyst only (C) Molecular mean free path only (D) Molecular velocity and pore radius of the catalyst

Last Answer : (D) Molecular velocity and pore radius of the catalyst

Which of the following factors control the deactivation of a porous catalyst pellet? (A) Decay reactions (B) Pore diffusion (C) Form of surface attack by poison (D) All (A), (B) and (C)

Description : Which of the following factors control the deactivation of a porous catalyst pellet? (A) Decay reactions (B) Pore diffusion (C) Form of surface attack by poison (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

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 determination of catalyst surface area and pore size distribution (C) A higher temperature favours the reaction of higher activation energy (D) A catalyst increases the potential energy barrier over which the reactants must pass to form products

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

Effectiveness factor (E) of a catalyst pellet is defined as, E = (actual rate within pore of the catalyst)/(rate if not snowed by pore diffusion), Effectiveness factor for a first order reaction is given by (where, T = Thiele modulus) (A) tan hT/T (B) tan T/T(C) tan hT/tan T(D) None of these

Description : Effectiveness factor (E) of a catalyst pellet is defined as, E = (actual rate within pore of the catalyst)/(rate if not snowed by pore diffusion), Effectiveness factor for a first order reaction is given by (where, T = Thiele modulus) (A) tan hT/T (B) tan T/T (C) tan hT/tan T (D) None of these

Last Answer : (A) tan hT/T

If a solid-gas non-catalytic reaction occurs at very high temperature, the rate controlling step is the __________ diffusion. (A) Film (B) Ash layer (C) Pore (D) None of these

Description : If a solid-gas non-catalytic reaction occurs at very high temperature, the rate controlling step is the __________ diffusion. (A) Film (B) Ash layer (C) Pore (D) None of these

Last Answer : (A) Film

Bed pressure drop in an air fluidised bed of catalyst particles (ρp = 200 kg/m3, Dp = 0.05 cm) of 60 cm bed depth and bed porosity of 0.5 expressed in cm of water (manometer) is (A) 90 (B) 60 (C) 45 (D) 30

Description : Bed pressure drop in an air fluidised bed of catalyst particles (ρp = 200 kg/m3, Dp = 0.05 cm) of 60 cm bed depth and bed porosity of 0.5 expressed in cm of water (manometer) is (A) 90 (B) 60 (C) 45 (D) 30

Last Answer : (B) 60

Promoter is added to the catalyst to improve its (A) Porosity (B) Sensitivity (C) Surface area (D) None of these

Description : Promoter is added to the catalyst to improve its (A) Porosity (B) Sensitivity (C) Surface area (D) None of these

Last Answer : (B) Sensitivity

Thermal conductivity of a conducting solid material depends upon its (A) Temperature (B) Porosity (C) Both (A) & (B) (D) Neither (A) nor (B)

Description : Thermal conductivity of a conducting solid material depends upon its (A) Temperature (B) Porosity (C) Both (A) & (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) & (B)

During coal carbonisation process, the conversion of semi-coke to coke is accompanied by an increase in the __________ of the mass. (A) Density (B) Porosity (C) Electrical resistivity (D) None of these

Description : During coal carbonisation process, the conversion of semi-coke to coke is accompanied by an increase in the __________ of the mass. (A) Density (B) Porosity (C) Electrical resistivity (D) None of these

Last Answer : (A) Density

"Micum Index" of a coke is a measure of its (A) Reactivity (B) Porosity (C) Bulk density (D) Hardness & strength

Description : "Micum Index" of a coke is a measure of its (A) Reactivity (B) Porosity (C) Bulk density (D) Hardness & strength

Last Answer : (D) Hardness & strength

A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle system (in SI units) is given below : Δ P/L = 375 × 10 3 VOM + 10.94 × 10 6 V2 OM (SI units) If water is to be used as the fluidising medium, the minimum fluidisation velocity, VOM is (A) 12 mm/s (B) 16 mm/s (C) 24 mm/s (D) 28 mm/s

Description : A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle ... fluidisation velocity, VOM is (A) 12 mm/s (B) 16 mm/s (C) 24 mm/s (D) 28 mm/s

Last Answer : (B) 16 mm/s

A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle system (in SI units) is given below: Δ P/L = 375 × 10 3 VOM + 10.94 × 10 6 V2 OM (SI units) If water is to be used as the fluidising medium, in actual operation, the above bed has a height = 1 m. What is the porosity of the fluidised bed? (A) 0.2 (B) 0.5 (C) 0.7 (D) 0.8

Description : A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle system ... What is the porosity of the fluidised bed? (A) 0.2 (B) 0.5 (C) 0.7 (D) 0.8

Last Answer : (C) 0.7

How can one determine the particle size distribution for a given bulk solid?

Description : How can one determine the particle size distribution for a given bulk solid?

Last Answer : While there are high-tech methods of performing such an analysis (laser-diffraction and video imaging system are available), the simplest way is to use a sieve stack. For example, to analyze a ... a combination of movements (shaken) to allow the solids to pass through the appropriate mesh sizes.

Density in the solid state is slightly less than that in its liquid state, in case of (A) Carbon dioxide (B) Water (C) Mercury (D) None of these

Description : Density in the solid state is slightly less than that in its liquid state, in case of (A) Carbon dioxide (B) Water (C) Mercury (D) None of these

Last Answer : (B) Water

What is the Thiele modulus of the solid catalysed first order reaction as shown in the bellow figure, if the pore diffusion offers negligible resistance to reaction? (A) < 5 (B) < 0.5(C) > 1 (D) 5

Description : What is the Thiele modulus of the solid catalysed first order reaction as shown in the bellow figure, if the pore diffusion offers negligible resistance to reaction? (A) < 5 (B) < 0.5 (C) > 1 (D) 5

Last Answer : (B) < 0.5

Which one is the rate controlling step in a solid-gas non-catalytic reaction occurring at very high temperature? (A) Pore diffusion (B) Film diffusion (C) Ash layer diffusion (D) Chemical reaction

Description : Which one is the rate controlling step in a solid-gas non-catalytic reaction occurring at very high temperature? (A) Pore diffusion (B) Film diffusion (C) Ash layer diffusion (D) Chemical reaction

Last Answer : (B) Film diffusion

Which of the following resistances is not involved in a gas phase catalytic (gas-solid) reaction?(A) Ash resistance (B) Gas film and pore surface diffusion resistances for reactants (C) Surface phenomenon resistance (D) Gas film and pore surface diffusion resistances for products

Description : Which of the following resistances is not involved in a gas phase catalytic (gas-solid) reaction? (A) Ash resistance (B) Gas film and pore surface diffusion resistances for reactants (C) Surface phenomenon resistance (D) Gas film and pore surface diffusion resistances for products

Last Answer : (A) Ash resistance

For a solid catalysed chemical reaction, the effectiveness of solid catalyst depends upon the __________ adsorption. (A) Physical (B) Chemical (C) Both (A) and (B) (D) Neither (A) nor (B)

Description : For a solid catalysed chemical reaction, the effectiveness of solid catalyst depends upon the __________ adsorption. (A) Physical (B) Chemical (C) Both (A) and (B) (D) Neither (A) nor (B)

Last Answer : (B) Chemical

Overall rate of reaction in a heterogeneous catalytic reaction depends upon the mass and energy transfer from the fluid to solid surface and its rate of reaction is usually __________ the concentration of catalyst, if it doesnot entail a chain mechanism.(A) Proportional to(B) Independent of(C) Inversely proportional to(D) Proportional to the square o

Description : Overall rate of reaction in a heterogeneous catalytic reaction depends upon the mass and energy transfer from the fluid to solid surface and its rate of reaction is usually __________ the concentration of ... to (B) Independent of (C) Inversely proportional to (D) Proportional to the square o

Last Answer : (A) Proportional to

With increase in porosity, the thermal conductivity of a solid substance (A) Increases (B) Decreases (C) Remains unchanged (D) May increase or decrease; depends on the solid

Description : With increase in porosity, the thermal conductivity of a solid substance (A) Increases (B) Decreases (C) Remains unchanged (D) May increase or decrease; depends on the solid

Last Answer : (B) Decreases

The neutral stress in a soil mass is (A) Force per neutral area (B) Force per effective area (C) Stress taken up by the pore water (D) Stress taken up by solid particles

Description : The neutral stress in a soil mass is (A) Force per neutral area (B) Force per effective area (C) Stress taken up by the pore water (D) Stress taken up by solid particles

Last Answer : Answer: Option C

Coke having higher porosity has (A) Lower bulk density (B) Lower strength (C) Higher reactivity (D) All (A), (B) and (C)

Description : Coke having higher porosity has (A) Lower bulk density (B) Lower strength (C) Higher reactivity (D) All (A), (B) and (C)

Last Answer : (D) All (A), (B) and (C)

A bed consists of particles of density 2000 kg/m3 . If the height of the bed is 1.5 metres and its porosity 0.6, the pressure drop required to fluidise the bed by air is (A) 25.61 kPa (B) 11.77 kPa (C) 14.86 kPa (D) 21.13 kPa

Description : A bed consists of particles of density 2000 kg/m3 . If the height of the bed is 1.5 metres and its porosity 0.6, the pressure drop required to fluidise the bed by air is (A) 25.61 kPa (B) 11.77 kPa (C) 14.86 kPa (D) 21.13 kPa

Last Answer : (B) 11.77 kPa

In Newton's law range, the terminal velocity of a solid spherical particle falling through a stationary fluid mass varies as the __________ of its diameter. (A) Inverse (B) Square root (C) Second power (D) First power

Description : In Newton's law range, the terminal velocity of a solid spherical particle falling through a stationary fluid mass varies as the __________ of its diameter. (A) Inverse (B) Square root (C) Second power (D) First power

Last Answer : (B) Square root

In the Newton's law range, the terminal velocity of a solid spherical particle falling through a stationary fluid mass is __________ the fluid viscosity. (A) Directly proportional to (B) Inversely proportional to (C) Inversely proportional to the square root of (D) Independent of

Description : In the Newton's law range, the terminal velocity of a solid spherical particle falling through a stationary fluid mass is __________ the fluid viscosity. (A) Directly proportional to (B) Inversely proportional to (C) Inversely proportional to the square root of (D) Independent of

Last Answer : (B) Inversely proportional to

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) Diffusion of the solute from the solution in contact with the particle to the main bulk of the solution (D) All 'a', 'b' & 'c'

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'

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)

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)

B.E.T. method of finding out surface area of a catalyst, uses the extension of __________ isotherm. (A) Langmuir (B) Freundlich (C) Tempkin (D) None of these

Description : B.E.T. method of finding out surface area of a catalyst, uses the extension of __________ isotherm. (A) Langmuir (B) Freundlich (C) Tempkin (D) None of these

Last Answer : (A) Langmuir

__________ gas is normally employed in B.E.T. method of finding out the surface area of catalyst. (A) N2 (B) H2(C) CO2(D) He

Description : __________ gas is normally employed in B.E.T. method of finding out the surface area of catalyst. (A) N2 (B) H2 (C) CO2 (D) He

Last Answer : (A) N2

To determine the state of charge of a nickel-cadmium battery, you should ___________. A. check the electrolyte with a hydrometer B. use the constant specific gravity method C. use a nonbreakable mercury thermometer D. connect a voltmeter to the battery terminals

Description : To determine the state of charge of a nickel-cadmium battery, you should ___________. A. check the electrolyte with a hydrometer B. use the constant specific gravity method C. use a nonbreakable mercury thermometer D. connect a voltmeter to the battery terminals

Last Answer : Answer: D

For shear strength, triaxial shear test is suitable because (A) It can be performed under all three drainage conditions (B) Precise measurement of the pore pressure and volume change during the test is possible (C) Stress distribution on the failure plane, is uniform (D) All the above

Description : For shear strength, triaxial shear test is suitable because (A) It can be performed under all three drainage conditions (B) Precise measurement of the pore pressure and volume change during the test is possible (C) Stress distribution on the failure plane, is uniform (D) All the above

Last Answer : (D) All the above

A triaxial shear test is preferred to direct shear test, because (A) It can be performed under all three drainage conditions with complete control (B) Precise measurement of pore pressure and change in volume during test, is not possible (C) Stress distribution on the failure plane, is non uniform (D) None of these

Description : A triaxial shear test is preferred to direct shear test, because (A) It can be performed under all three drainage conditions with complete control (B) Precise measurement of pore pressure and change in ... possible (C) Stress distribution on the failure plane, is non uniform (D) None of these

Last Answer : Answer: Option A

Pore size of the molecular sieve 5A is __________ mm. (A) 5 (B) 0.5 (C) 0.05 (D) 50

Description : Pore size of the molecular sieve 5A is __________ mm. (A) 5 (B) 0.5 (C) 0.05 (D) 50

Last Answer : (B) 0.5

The capacity of a classifier in 'tons of solid/hr' is given by (where, A = cross-sectional area in m2 , V = rising velocity of fluid in m/sec, S = percentage of solids in the suspension by volume, ρ = density of solids in kg/m3 ) (A) 3.6 AVS.ρ (B) 3.6 A.V.ρ (C) 3.6 A.S. ρ (D) 3.6 AVS/ρ

Description : The capacity of a classifier in 'tons of solid/hr' is given by (where, A = cross-sectional area in m2 , V = rising velocity of fluid in m/sec, S = percentage of solids in the suspension by volume, ρ = density of solids in kg/m3 ) (A) 3.6 AVS.ρ (B) 3.6 A.V.ρ (C) 3.6 A.S. ρ (D) 3.6 AVS/ρ

Last Answer : (A) 3.6 AVS.ρ