Pick out the wrong statement about the machinability of metals. Machinability of a metal (A) Decreases with increase in strain hardening tendencies (B) Decreases with increase in hardness, in general (C) Depend on the composition, microstructure and physical & mechanical

Pick out the wrong statement about the machinability of metals.
Machinability of a metal
(A) Decreases with increase in strain hardening tendencies
(B) Decreases with increase in hardness, in general
(C) Depend on the composition, microstructure and physical & mechanical
by

1 Answer

Answer :

Option C
by

Related questions

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 the decrease in electron movement (C) Recrystallisation temperature decreases with decrease in strain in a cold worked metal (D) With increase in temperature, the electrical conductivity of intrinsic semi-conductor will increase

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

In cold working of metal as compared to its hot working (A) Cracks and blow holes are eliminated (B) Ductility and impact strength improves (C) Appreciable strain hardening is produced (D) Yield stress, hardness and fatigue strength is not at all affected

Description : In cold working of metal as compared to its hot working (A) Cracks and blow holes are eliminated (B) Ductility and impact strength improves (C) Appreciable strain hardening is produced (D) Yield stress, hardness and fatigue strength is not at all affected

Last Answer : (C) Appreciable strain hardening is produced

Pick up the correct statement from the following: (A) Catalysts are added to assist and accelerate the hardening of resin (B) The fillers are inert materials and they impart strength and hardness (C) Fibrous fillers increase thermal resistance (D) All the above

Description : Pick up the correct statement from the following: (A) Catalysts are added to assist and accelerate the hardening of resin (B) The fillers are inert materials and they impart strength and hardness (C) Fibrous fillers increase thermal resistance (D) All the above

Last Answer : Answer: Option D

Pick out the wrong statement. (A) Addition of methane to the furnace atmosphere reduces decarburising by hydrogen (B) Nitrogen in presence of steam decor-burises high carbon steel, whereas hydrocarbon gases carburise the surface of steel at annealing temperatures (C) Active nitrogen (formed by cracking ammonia at the metal surface) cause nitride formation with increase in surface hardness (D) None of these

Description : Pick out the wrong statement. (A) Addition of methane to the furnace atmosphere reduces decarburising by hydrogen (B) Nitrogen in presence of steam decor-burises high carbon steel, whereas hydrocarbon ... the metal surface) cause nitride formation with increase in surface hardness (D) None of these

Last Answer : (D) None of these

The increase in hardness of metal due to its cold working is termed as the __________ hardening. (A) Work (B) Age (C) Induction (D) Flame

Description : The increase in hardness of metal due to its cold working is termed as the __________ hardening. (A) Work (B) Age (C) Induction (D) Flame

Last Answer : (A) Work

Strain hardening effect in metals subjected to cold working is due to the __________ mechanism. (A) Slip (B) Fracture (C) Winning (D) Dislocation

Description : Strain hardening effect in metals subjected to cold working is due to the __________ mechanism. (A) Slip (B) Fracture (C) Winning (D) Dislocation

Last Answer : (D) Dislocation

Babbitt metals used for making bearings are (A) Tin or lead based alloys (B) Short of antifrictional properties (C) Having homogenous microstructure (D) Yellow metals

Description : Babbitt metals used for making bearings are (A) Tin or lead based alloys (B) Short of antifrictional properties (C) Having homogenous microstructure (D) Yellow metals

Last Answer : (A) Tin or lead based alloys

Pick out the wrong statement about coating/electroplating of metals. (A) Phosphate coating is used as an excellent base for paints & enamels (B) Phosphate coating is less corrosion resistant than chromate coating (C) The base metal to be electroplated is normally made the cathode of the electrolytic cell and coating metal is made the anode (D) Calorising is the process of coating steel with chromium

Description : Pick out the wrong statement about coating/electroplating of metals. (A) Phosphate coating is used as an excellent base for paints & enamels (B) Phosphate coating is less corrosion resistant than ... coating metal is made the anode (D) Calorising is the process of coating steel with chromium

Last Answer : (D) Calorising is the process of coating steel with chromium

Pick out the wrong statement. (A) Copper is the metal having the highest electronic conductivity (B) Hardenability & Weldability of metals are inversely related (C) Covalent bonding formed by sharing of electrons is present in all semiconductor materials (D) Glass transition temperature applies to 'polymers' but not to 'glasses'

Description : Pick out the wrong statement. (A) Copper is the metal having the highest electronic conductivity (B) Hardenability & Weldability of metals are inversely related (C) Covalent bonding formed by ... all semiconductor materials (D) Glass transition temperature applies to 'polymers' but not to 'glasses'

Last Answer : Option A

Addition of nickel to copper improves its (A) Machinability (B) Ductility (C) Strength (D) Hardness

Description : Addition of nickel to copper improves its (A) Machinability (B) Ductility (C) Strength (D) Hardness

Last Answer : (D) Hardness

Strain hardening effect in a metal subjected to cold working is due to the __________ mechanism. (A) Fracture (B) Dislocation (C) Slip (D) Twinning

Description : Strain hardening effect in a metal subjected to cold working is due to the __________ mechanism. (A) Fracture (B) Dislocation (C) Slip (D) Twinning

Last Answer : (C) Slip

Cold working of a material results in increase in hardness, which is termed as the __________ hardening. (A) Cold (B) Work (C) Age (D) Induction

Description : Cold working of a material results in increase in hardness, which is termed as the __________ hardening. (A) Cold (B) Work (C) Age (D) Induction

Last Answer : (B) Work

Define the terms: i) Hardness ii) Toughness iii) Brazing iv) Machinability

Description : Define the terms: i) Hardness ii) Toughness iii) Brazing iv) Machinability

Last Answer : i) Hardness:- Hardness is the property of metal possessed by a material which enables it to resist penetration or abrasion or scratching by other material. Diamond is the hardest of known materials.  ... can be easily cut by cutting tools to produce a desired shape & surface finish on its surface

Between 230 and 370°C, blue brittleness is caused in mild steel because of the (A) Immobility of dislocation (B) Strain-ageing (C) Increase in Young's modulus (D) Strain hardening

Description : Between 230 and 370°C, blue brittleness is caused in mild steel because of the (A) Immobility of dislocation (B) Strain-ageing (C) Increase in Young's modulus (D) Strain hardening

Last Answer : Option B

Pick out the correct statement. (A) Stainless steel is nothing but chromium coated steel (B) Hardening of a soft metal can be done by alloying it with another metal or non-metal (C) Plastic deformation of a material is its temporary distortion under the action of applied stress (D) Rusting of iron is not electrochemical in nature

Description : Pick out the correct statement. (A) Stainless steel is nothing but chromium coated steel (B) Hardening of a soft metal can be done by alloying it with another metal or non-metal (C) ... its temporary distortion under the action of applied stress (D) Rusting of iron is not electrochemical in nature

Last Answer : (B) Hardening of a soft metal can be done by alloying it with another metal or non-metal

Pick out the wrong statement (A) Hardening makes the steel more brittle (B) High alloy steels contain more than 50% alloying element (C) 18/8 stainless steel is a magnetic steel (D) Both (B) and (C)

Description : Pick out the wrong statement (A) Hardening makes the steel more brittle (B) High alloy steels contain more than 50% alloying element (C) 18/8 stainless steel is a magnetic steel (D) Both (B) and (C)

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

__________ of a material results, when its strength is increased & ductility is decreased by heating at a relatively lower temperature after cold working. (A) Solid solution hardening (B) Screw dislocation (C) Strain ageing (D) Twinning

Description : __________ of a material results, when its strength is increased & ductility is decreased by heating at a relatively lower temperature after cold working. (A) Solid solution hardening (B) Screw dislocation (C) Strain ageing (D) Twinning

Last Answer : (C) Strain ageing

Normalising does not __________ of a metal. (A) Improve machinability & tensile strength (B) Remove internal stresses (C) Refine the structure (D) Remove strains caused by cold working

Description : Normalising does not __________ of a metal. (A) Improve machinability & tensile strength (B) Remove internal stresses (C) Refine the structure (D) Remove strains caused by cold working

Last Answer : Option B

Pick out the wrong statement pertaining to the cooling towers. (A) In case of induced draft cooling tower, the fan is placed at the top of the tower (B) Effectiveness of forced draft cooling tower is reduced by the recirculation of the humid and hot discharged air (C) A natural draft cooling tower is recommended to be used, when the air humidity is low and air temperature is also low (D) Effectiveness of a mechanical draft cooling tower is reduced with increase in air wet-bulb temperature

Description : Pick out the wrong statement pertaining to the cooling towers. (A) In case of induced draft cooling tower, the fan is placed at the top of the tower (B) Effectiveness of ... Effectiveness of a mechanical draft cooling tower is reduced with increase in air wet-bulb temperature

Last Answer : (D) Effectiveness of a mechanical draft cooling tower is reduced with increase in air wet-bulb temperature

Pick out the wrong statement. (A) The toughness of a material decreases, when it is heated (B) Crane hooks are normally made of wrought iron (C) Cold working of a metal decreases its fatigue strength (D) The temperature at which new grains are formed in a metal is known as the recrystallisation temperature

Description : Pick out the wrong statement. (A) The toughness of a material decreases, when it is heated (B) Crane hooks are normally made of wrought iron (C) Cold working of a metal decreases its ... (D) The temperature at which new grains are formed in a metal is known as the recrystallisation temperature

Last Answer : (C) Cold working of a metal decreases its fatigue strength

Pick out the wrong statement. (A) LPG is also used as fuel for automobiles & small furnaces and for cutting & welding of metals (B) The minimum temperature, at which a petroleum oil vapor catches fire and continues to burn, is called its flash point (C) Each ton of petroleum oil on distillation produces about 30-50 Nm3 of gas (D) Maximum yield of naphthalene is obtained on distillation of crude oil

Description : Pick out the wrong statement. (A) LPG is also used as fuel for automobiles & small furnaces and for cutting & welding of metals (B) The minimum temperature, at which a petroleum oil vapor catches ... about 30-50 Nm3 of gas (D) Maximum yield of naphthalene is obtained on distillation of crude oil

Last Answer : (B) The minimum temperature, at which a petroleum oil vapor catches fire and continues to burn, is called its flash point

With increase in carbide/graphite ratio in cast iron, its (A) Hardness & brittleness increases (B) Ductility decreases (C) Both (A) and (B) (D) Neither (A) nor (B)

Description : With increase in carbide/graphite ratio in cast iron, its (A) Hardness & brittleness increases (B) Ductility decreases (C) Both (A) and (B) (D) Neither (A) nor (B)

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

Pick out the wrong statement. (A) Cokes of high reactivity are obtained from weakly coking coals (B) Cokes of high reactivity are obtained from strongly coking coals (C) Reactivity of coke is inversely proportional to its absolute density (D) Abrasion index of the coke is a measure of its hardness

Description : Pick out the wrong statement. (A) Cokes of high reactivity are obtained from weakly coking coals (B) Cokes of high reactivity are obtained from strongly coking coals (C) Reactivity of coke is inversely proportional to its absolute density (D) Abrasion index of the coke is a measure of its hardness

Last Answer : (B) Cokes of high reactivity are obtained from strongly coking coals

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 aliphatic character are more soluble in aliphatic solvents, while those polymers having more aromatic character are more soluble in aromatic solvents (C) Swelling tendency or solubility of polymers in a particular solvent decreases with increase in molecular weight of the solvent (D) High molecular weight polymers on dissolving gives solution of very low viscosity

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

Pick out the wrong statement. (A) Hammer crushers operate by impact action (B) Standard screens have circular opening (C) With increase in mesh number of screens, their diameter in microns decreases (D) 200 mesh screen has 200 openings per linear cm

Description : Pick out the wrong statement. (A) Hammer crushers operate by impact action (B) Standard screens have circular opening (C) With increase in mesh number of screens, their diameter in microns decreases (D) 200 mesh screen has 200 openings per linear cm

Last Answer : (D) 200 mesh screen has 200 openings per linear cm

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

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

Pick out the wrong statement. (A) The emissivity of a surface decreases, if it gets corroded by atmospheric environment (B) The emissivity of a surface increases with increase in surface roughness (C) The emissivity of a polished surface is quite low (D) The emissivity of a non-metallic surface decreases with increase in the temperature

Description : Pick out the wrong statement. (A) The emissivity of a surface decreases, if it gets corroded by atmospheric environment (B) The emissivity of a surface increases with increase in surface roughness ... quite low (D) The emissivity of a non-metallic surface decreases with increase in the temperature

Last Answer : (A) The emissivity of a surface decreases, if it gets corroded by atmospheric environment

Pick out the wrong statement. (A) The shear stress at the pipe (dia = D, length = L) wall in case of laminar flow of Newtonian fluids is (D/4L). ∆p (B) In the equation, T. gc = k. (du/dy) n the value of 'n' for pseudoplastic and Dilatant fluid are < 1 and >1 respectively (C) Shear stress for Newtonian fluid is proportional to the rate of shear in the direction perpendicular to motion (D) With increase in the Mach number >0.6, the drag co-efficient decreases in case of compressible fluids

Description : Pick out the wrong statement. (A) The shear stress at the pipe (dia = D, length = L) wall in case of laminar flow of Newtonian fluids is (D/4L). ∆p (B) In the equation, T. gc = k. ... to motion (D) With increase in the Mach number >0.6, the drag co-efficient decreases in case of compressible fluids

Last Answer : (D) With increase in the Mach number >0.6, the drag co-efficient decreases in case of compressible fluids

Case hardening of a material is (A) Followed by tempering or carburising (B) Preceded by its tempering (C) Done to get a soft ductile interior with a very hard surface (D) Carried out to get extreme hardness in its core

Description : Case hardening of a material is (A) Followed by tempering or carburising (B) Preceded by its tempering (C) Done to get a soft ductile interior with a very hard surface (D) Carried out to get extreme hardness in its core

Last Answer : (D) Carried out to get extreme hardness in its core

Exposure to SO2 containing chimney gases results in the (A) Reduction in strength of leather & cloth (B) Acceleration of corrosion rates of metals (C) Increased drying & hardening time of paints (D) All (A), (B) and (C)

Description : Exposure to SO2 containing chimney gases results in the (A) Reduction in strength of leather & cloth (B) Acceleration of corrosion rates of metals (C) Increased drying & hardening time of paints (D) All (A), (B) and (C)

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

Pick out the wrong statement. (A) Cold cracking of a weld is due to the presence of hydrogen gas in the weld (B) True stress is given by, σ = σE (1 + εE), where σE and εE are engineering stress and engineering strain respectively (C) Phosphorous can be easily recovered in the iron blast furnace (D) High residual stress at the surface is beneficial for fatigue properties of a material

Description : Pick out the wrong statement. (A) Cold cracking of a weld is due to the presence of hydrogen gas in the weld (B) True stress is given by, σ = σE (1 + εE), where σE and εE ... in the iron blast furnace (D) High residual stress at the surface is beneficial for fatigue properties of a material

Last Answer : Option C

To counteract the bad effects of strain hardening on a cold formed part, it must be (A) Tempered (B) Normalised (C) Annealed (D) Hardened

Description : To counteract the bad effects of strain hardening on a cold formed part, it must be (A) Tempered (B) Normalised (C) Annealed (D) Hardened

Last Answer : Option C

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 pressure distribution of both components is nonlinear in the case of steady state unimolal unidirectional diffusion (C) Azeotropes obey Raoult's law at all temperature (D) The relative volatility of a binary mixture at the Azeotropic composition is 1

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

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 temperature (C) The relative volatility of a binary mixture at Azeotropic composition is unity (D) Flash distillation is practised on wide spread scale in petroleum refinery

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

Pick out the wrong statement. (A) In a batch reactor, which is exclusively used for liquid phase reactions; temperature pressure and composition may vary with time (B) In a semi-batch reactor, one reactant is charged batch wise, while the other reactant is fed continuously (C) In a continuous flow reactor, uniform concentration cannot be maintained throughout the vessel even in a well agitated system (D) In a continuous flow reactor, both the reactants and the products flow out continuously

Description : Pick out the wrong statement. (A) In a batch reactor, which is exclusively used for liquid phase reactions; temperature pressure and composition may vary with time (B) In a semi-batch reactor, ... system (D) In a continuous flow reactor, both the reactants and the products flow out continuously

Last Answer : (C) In a continuous flow reactor, uniform concentration cannot be maintained throughout the vessel even in a well agitated system

Pick out the wrong statement. (A) The integral method of analysing kinetic data is used when the data is scattered (B) The differential method of analysing kinetic data requires more accurate or larger amounts of data (C) When the reaction rate is independent of temperature, the reaction is said to be of zero order (D) The ratio of volumes of plug flow reactor to that of mixed reactor is always less than one for identical feed composition, flow rate, conversion and for all positive reaction orders

Description : Pick out the wrong statement. (A) The integral method of analysing kinetic data is used when the data is scattered (B) The differential method of analysing kinetic data requires more accurate ... less than one for identical feed composition, flow rate, conversion and for all positive reaction orders

Last Answer : (C) When the reaction rate is independent of temperature, the reaction is said to be of zero order

Pick out the wrong statement. (A) Use of different catalysts in a reversible catalytic chemical reaction does not change the equilibrium composition (B) Alumina is added as a promoter to iron catalyst in ammonia synthesis reaction (C) Activation energy for a reaction is obtained from the intercept of the Arrhenius plot (D) Presence of inerts affects the equilibrium conversion of reactants in a chemical reaction

Description : Pick out the wrong statement. (A) Use of different catalysts in a reversible catalytic chemical reaction does not change the equilibrium composition (B) Alumina is added as a promoter to ... Arrhenius plot (D) Presence of inerts affects the equilibrium conversion of reactants in a chemical reaction

Last Answer : (C) Activation energy for a reaction is obtained from the intercept of the Arrhenius plot

Pick out the wrong statement. (A) A catalyst does not alter the final position of equilibrium in a reversible reaction (B) A catalyst initiates a reaction (C) A catalyst is specific in reaction (D) A catalyst remains unchanged in chemical composition at the end the reaction

Description : Pick out the wrong statement. (A) A catalyst does not alter the final position of equilibrium in a reversible reaction (B) A catalyst initiates a reaction (C) A catalyst is specific in reaction (D) A catalyst remains unchanged in chemical composition at the end the reaction

Last Answer : (B) A catalyst initiates a reaction

Pick out the true statement pertaining to water treatment. (A) Slow sand filters can remove colour completely (B) Activated carbon can be used for taste & odour control without subsequent filtration (C) Application of activated carbon reduces the temporary hardness of water (D) Normally, the turbidity is removed by adding a coagulant prior to sedimentation

Description : Pick out the true statement pertaining to water treatment. (A) Slow sand filters can remove colour completely (B) Activated carbon can be used for taste & odour control without subsequent filtration ... of water (D) Normally, the turbidity is removed by adding a coagulant prior to sedimentation

Last Answer : (D) Normally, the turbidity is removed by adding a coagulant prior to sedimentation

Pick out the correct statement. (A) Hot worked materials are subjected to annealing to remove internal stresses (B) Annealing of steel hardens it slightly (C) Normalising of a material induces stresses (D) Tempering of a material improves ductility & toughness but reduces hardness & brittleness

Description : Pick out the correct statement. (A) Hot worked materials are subjected to annealing to remove internal stresses (B) Annealing of steel hardens it slightly (C) Normalising of a material induces stresses (D) Tempering of a material improves ductility & toughness but reduces hardness & brittleness

Last Answer : (D) Tempering of a material improves ductility & toughness but reduces hardness & brittleness Share

In connection with corrosion of metals, passivation is the process that (A) Intensifies deterioration (B) Changes the composition of the metal (C) Inhibits further deterioration (D) None of these

Description : In connection with corrosion of metals, passivation is the process that (A) Intensifies deterioration (B) Changes the composition of the metal (C) Inhibits further deterioration (D) None of these

Last Answer : (C) Inhibits further deterioration

Pick out the wrong statement. (A) Metal/alloys having hexagonal crystal lattice structure are less malleable than those having cubic crystal lattice structure (B) Metal/alloys having body centred cubic (bcc) crystal lattice structure is stronger & less ductile than those having face centred cubic (fcc) crystal lattice structure (C) Tungsten has a body centred cubic (bcc) crystal lattice structure (D) Both ferritic & austenitic stainless steel has a face centred cubic (fcc) crystal structure

Description : Pick out the wrong statement. (A) Metal/alloys having hexagonal crystal lattice structure are less malleable than those having cubic crystal lattice structure (B) Metal/alloys having body centred cubic ... D) Both ferritic & austenitic stainless steel has a face centred cubic (fcc) crystal structure

Last Answer : (C) Tungsten has a body centred cubic (bcc) crystal lattice structure

Pick out the wrong statement. (A) Recycled coarse material to the grinder by a classifier is termed as circulating load (B) Wear and tear in wet crushing is more than that in dry crushing of materials (C) Size enlargement (opposite of size reduction) is not a mechanical operation (D) A 'dust catcher' is simply an enlargement in a pipeline which permits the solids to settle down due to reduction in velocity of the dust laden gas

Description : Pick out the wrong statement. (A) Recycled coarse material to the grinder by a classifier is termed as circulating load (B) Wear and tear in wet crushing is more than that in dry crushing of ... a pipeline which permits the solids to settle down due to reduction in velocity of the dust laden gas

Last Answer : (C) Size enlargement (opposite of size reduction) is not a mechanical operation

Pick out the wrong statement. (A) Close circuit grinding is more economical than open circuit grinding (B) Cod oil, beef tallow or aluminium stearates are used as grinding aids in cement 'industries' (C) The equipment used for the removal of traces of solids from a liquid is called a classifier (D) Size enlargement is a mechanical operation exemplified by medicinal tablet making

Description : Pick out the wrong statement. (A) Close circuit grinding is more economical than open circuit grinding (B) Cod oil, beef tallow or aluminium stearates are used as grinding aids in cement ... is called a classifier (D) Size enlargement is a mechanical operation exemplified by medicinal tablet making

Last Answer : (C) The equipment used for the removal of traces of solids from a liquid is called a classifier

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 interfacial tension (C) When Henry's law constant is very small, then the mass transfer rate is controlled by the gas film resistance (D) Taylor-Prandtl analogy for heat and mass transfer considers the transfer through both laminar and turbulent layers

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

Pick out the wrong statement pertaining to nitric acid. (A) About 90% of nitric acid is manufactured by Ostwald's process (B) It is a strong mono basic acid which reacts with almost all the metals except noble metals (C) Yellow color of impure nitric acid is because of dissolved oxides of nitrogen (mainly NO2 ) (D) Arc process of nitric acid manufacture is economical as compared to Ostwald's process

Description : Pick out the wrong statement pertaining to nitric acid. (A) About 90% of nitric acid is manufactured by Ostwald's process (B) It is a strong mono basic acid which reacts with almost all the ... (mainly NO2 ) (D) Arc process of nitric acid manufacture is economical as compared to Ostwald's process

Last Answer : (D) Arc process of nitric acid manufacture is economical as compared to Ostwald's process

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) Solders generally melt at less than 185°C (D) Steel produced by B.O.F process is ideally suited for manufacturing flat product

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

Increase in ash content of blast furnace coke (A) Reduces its consumption in the furnace (B) Increases its consumption in the furnace (C) Does not affect its consumption in the furnace (D) Decreases its hardness and abrasion resistance

Description : Increase in ash content of blast furnace coke (A) Reduces its consumption in the furnace (B) Increases its consumption in the furnace (C) Does not affect its consumption in the furnace (D) Decreases its hardness and abrasion resistance

Last Answer : (B) Increases its consumption in the furnace

Blowdown in a cooling tower (A) Means discarding a small fraction of circulating water to prevent and limit the concentration of salt and impurities (B) Increases the scale forming tendencies of water (C) Is undesirable (D) All (A), (B) & (C)

Description : Blowdown in a cooling tower (A) Means discarding a small fraction of circulating water to prevent and limit the concentration of salt and impurities (B) Increases the scale forming tendencies of water (C) Is undesirable (D) All (A), (B) & (C)

Last Answer : (A) Means discarding a small fraction of circulating water to prevent and limit the concentration of salt and impurities