Make up water is supplied during cooling tower operation to compensate for water losses due to
Make up water is supplied during cooling tower operation to compensate for water losses due to
When the mixture to be distilled has a very high boiling point and the product material is heat sensitive, the separation technique to be used is __________ distillation.
When the mixture to be distilled has a very high boiling point and the product material is heat sensitive, the separation technique to be used is __________ distillation.
Batch tray dryers suffers from the disadvantage of
Batch tray dryers suffers from the disadvantage of
__________ extractor uses centrifugal force for separating the two phases.
__________ extractor uses centrifugal force for separating the two phases.
Mass transfer co-efficient varies as DAB0.5, according to the __________ theory.
Mass transfer co-efficient varies as DAB0.5, according to the __________ theory.
Steady state temperature reached by a small amount of liquid evaporating into a large amount of unsaturated vapour-gas mixture is called the __________ temperature.
Steady state temperature reached by a small amount of liquid evaporating into a large amount of unsaturated vapour-gas mixture is called the __________ temperature.
When the __________ the relative humidity of air decreases, despite an increase in the absolute humidity.
When the __________ the relative humidity of air decreases, despite an increase in the absolute humidity.
During constant rate period, the rate of drying decreases with the
During constant rate period, the rate of drying decreases with the
In liquid-liquid extraction, the number of phases at plait point is
In liquid-liquid extraction, the number of phases at plait point is
At 750°K and 1 atm, the approximate value of Schmidt number for air is
At 750°K and 1 atm, the approximate value of Schmidt number for air is
Very tall packed towers are divided into series of beds to
Very tall packed towers are divided into series of beds to
Weeping in a distillation column
Weeping in a distillation column
Flooding results in
Flooding results in
When the solvent dissolves very little of solute, then
When the solvent dissolves very little of solute, then
Steady state equimolal counter diffusion occurs in case of
Steady state equimolal counter diffusion occurs in case of
Which of the following adsorbant is used in the refinning of sugar?
Which of the following adsorbant is used in the refinning of sugar?
A plait point is the point on the solubility curve, where the tie line reduces to a point. What is the number of plait point for a ternery system containing twopairs of partially miscible liquids?
A plait point is the point on the solubility curve, where the tie line reduces to a point. What is the number of plait point for a ternery system containing twopairs of partially miscible liquids?
The reason for preferring packed towers over plate towers in distillation practice is that the packed tower operation gives
The reason for preferring packed towers over plate towers in distillation practice is that the packed tower operation gives
At constant pressure, with increase of temperature, the dew point will
At constant pressure, with increase of temperature, the dew point will
Heat sensitive materials with very high latent heat of vaporisation may be economically separated using
Heat sensitive materials with very high latent heat of vaporisation may be economically separated using
The term "approach" in a cooling tower refers to the difference in the temperature of the
The term "approach" in a cooling tower refers to the difference in the temperature of the
Absorption factor method is used to calculate the number of ideal stages, when
Absorption factor method is used to calculate the number of ideal stages, when
Relative humidity is the ratio of the
Relative humidity is the ratio of the
Flash distillation is suitable for separating the constituents of a binary system, which
Flash distillation is suitable for separating the constituents of a binary system, which
For a distillation column operating at minimum reflux, the
For a distillation column operating at minimum reflux, the
Flash distillation is
Flash distillation is
At a given equilibrium pressure, with increase in temperature, the concentration of adsorbed gas on solid adsorbant
At a given equilibrium pressure, with increase in temperature, the concentration of adsorbed gas on solid adsorbant
Which of the following psychrometric processes is followed by water vapour laden unsaturated air, when it is passed through solid or liquid adsorbent?
Which of the following psychrometric processes is followed by water vapour laden unsaturated air, when it is passed through solid or liquid adsorbent?
The term "cooling range" in a cooling tower refers to the difference in the temperature of
The term "cooling range" in a cooling tower refers to the difference in the temperature of
Pick out the wrong statement.
Pick out the wrong statement.
Humidification involves mass transfer between a pure liquid phase and a fixed gas, which is
Humidification involves mass transfer between a pure liquid phase and a fixed gas, which is
During dehumidification of unsaturated air wet bulb temperature & partial pressure of vapor are not constant. However, during evaporative cooling process with recirculated water supply, the __________ remains constant.
During dehumidification of unsaturated air wet bulb temperature & partial pressure of vapor are not constant. However, during evaporative cooling process with recirculated water supply, the __________ remains constant.
Ion exchange process is similar to
Ion exchange process is similar to
For __________ drying, the effects of velocity, temperature and humidity of the gas and the thickness of the solid are the same.
For __________ drying, the effects of velocity, temperature and humidity of the gas and the thickness of the solid are the same.
The critical moisture content in case of drying indicates the __________ rate period.
The critical moisture content in case of drying indicates the __________ rate period.
__________ number indicates the ratio of the rates of the heat and mass transfer incase of a cooling tower.
__________ number indicates the ratio of the rates of the heat and mass transfer incase of a cooling tower.
Hypersorption refers to a __________ process.
Hypersorption refers to a __________ process.
Molecular diffusivity of a liquid
Molecular diffusivity of a liquid
In McCabe-Thiele method of theoretical plate calculation for a distillation column, the operating lines of stripping and rectifying sections coincide with the diagonal at __________ reflux.
In McCabe-Thiele method of theoretical plate calculation for a distillation column, the operating lines of stripping and rectifying sections coincide with the diagonal at __________ reflux.
Drift in a cooling tower is
Drift in a cooling tower is
Rayleigh's equation applies to __________ distillation.
Rayleigh's equation applies to __________ distillation.
The wet and 'dry bulb temperature for a vapour-gas mixture are 25°C and 30°C respectively. If the mixture is heated to 45°C at constant pressure, the wet bulb temperature will be __________ °C.
The wet and 'dry bulb temperature for a vapour-gas mixture are 25°C and 30°C respectively. If the mixture is heated to 45°C at constant pressure, the wet bulb temperature will be __________ °C.
The caking of crystals can be prevented by
The caking of crystals can be prevented by
To remove all the moisture from a wet solid it requires exposure to __________ air.
To remove all the moisture from a wet solid it requires exposure to __________ air.
Fractional solvent extraction
Fractional solvent extraction
Plate efficiency in a distillation column is reduced due to the __________ of liquid.
Plate efficiency in a distillation column is reduced due to the __________ of liquid.
In a single stage extraction process, 10 kg of pure solvent S (containing no solute A) is mixed with 30 kg of feed F containing A at a mass fraction xf = 0.2. The mixture splits into an extract phase E and a raf-finate phase R containing A at xB = 0.5 and xR = 0.05 respectively. The total mass of the extract phase is (in Kg)
In a single stage extraction process, 10 kg of pure solvent S (containing no solute A) is mixed with 30 kg of feed F containing A at a mass fraction xf = 0.2. The mixture splits into an extract phase E and a raf-finate phase R containing A at xB = 0.5 and xR = 0.05 respectively. The total mass of the extract phase is (in Kg)
Pick out the wrong statement.
Pick out the wrong statement.
Pick out the wrong statement.
Pick out the wrong statement.
Steam distillation is used for separation of high boiling
Steam distillation is used for separation of high boiling
Liquid diffusivity is of the order of __________ cm² /second.
Liquid diffusivity is of the order of __________ cm² /second.
Leaching of coffee from coffee beans is done by
Leaching of coffee from coffee beans is done by
For contacting a highly soluble gas with a liquid
For contacting a highly soluble gas with a liquid
Pick out the wrong statement.
Pick out the wrong statement.
Large scale usage of flash distillation is practised in
Large scale usage of flash distillation is practised in
A pure drug is administered as a sphere and as a cube. The amount of drug is the same in the two tablets. Assuming that the shape and size do not influence the mass transfer, the ratio of rate of dissolution in water at t = 0 for the cubic to spherical tablet is
A pure drug is administered as a sphere and as a cube. The amount of drug is the same in the two tablets. Assuming that the shape and size do not influence the mass transfer, the ratio of rate of dissolution in water at t = 0 for the cubic to spherical tablet is
The Kundsen diffusivity is proportional to (where, T = absolute temperature)
The Kundsen diffusivity is proportional to (where, T = absolute temperature)
For a binary mixture with low relative volatility, continuous rectification to get pure products will require
For a binary mixture with low relative volatility, continuous rectification to get pure products will require
The temperature to which a vapour gas mixture must be cooled (at varying humidity) to become saturated is called the __________ temperature.
The temperature to which a vapour gas mixture must be cooled (at varying humidity) to become saturated is called the __________ temperature.
The partial pressure distribution of an ideal gas diffusing through another stagnant ideal gas at steady state follows a/an __________ law.
The partial pressure distribution of an ideal gas diffusing through another stagnant ideal gas at steady state follows a/an __________ law.
Pick out the wrong statement pertaining to the rotary dryer.
Pick out the wrong statement pertaining to the rotary dryer.
Inside the distillation column, the
Inside the distillation column, the
The binary diffusivity in gases does not depend upon the
The binary diffusivity in gases does not depend upon the
It takes 6 hours to dry a wet solid from 50% moisture content to the critical moisture content of 15%. How much longer it will take to dry the solid to 10% moisture content, under the same drying conditions? (The equilibrium moisture content of the solid is 5%).
It takes 6 hours to dry a wet solid from 50% moisture content to the critical moisture content of 15%. How much longer it will take to dry the solid to 10% moisture content, under the same drying conditions? (The equilibrium moisture content of the solid is 5%).
During constant rate drying period, vaporisation rate per unit drying surface area
During constant rate drying period, vaporisation rate per unit drying surface area
During drying operation, it is easier to remove the __________ moisture.
During drying operation, it is easier to remove the __________ moisture.
Mechanism of moisture removal in case of freeze drying of food stuff is by
Mechanism of moisture removal in case of freeze drying of food stuff is by
For turbulent mass transfer in pipes, the Sherwood number depends on the Reynolds number as
For turbulent mass transfer in pipes, the Sherwood number depends on the Reynolds number as
Berl saddle made of carbon cannot be used for
Berl saddle made of carbon cannot be used for
The Hatta number is important in
The Hatta number is important in
In gas-liquid contact operation, the number of ideal stages, N = (xa - xb)/(xb - x*b) . This is true when the stripping factor 'S' is
In gas-liquid contact operation, the number of ideal stages, N = (xa - xb)/(xb - x*b) . This is true when the stripping factor 'S' is
Which of the following is considered equivalent to one theoretical stage in Mc-Cabe Thiele's method?
Which of the following is considered equivalent to one theoretical stage in Mc-Cabe Thiele's method?
A 25 cm x 25 cm x 1 cm flat sheet weighing 1.2 kg initially was dried from both sides under constant drying rate conditions. It took 1500 seconds for the weight of the sheet to reduce to 1.05 kg. Another 1m x 1m x 1cm flat sheet of the same material is to be dried from one side only.Under the same constant drying rate conditions, the time required for drying (in seconds) from its initial weight of 19.2 kg to 17.6 kg is
A 25 cm x 25 cm x 1 cm flat sheet weighing 1.2 kg initially was dried from both sides under constant drying rate conditions. It took 1500 seconds for the weight of the sheet to reduce to 1.05 kg. Another 1m x 1m x 1cm flat sheet of the same material is to be dried from one side only.Under the same constant drying rate conditions, the time required for drying (in seconds) from its initial weight of 19.2 kg to 17.6 kg is
Which of the following gas-liquid contacting devices incurs the least pressure drop for a particular duty?
Which of the following gas-liquid contacting devices incurs the least pressure drop for a particular duty?
Mass transfer co-efficient is defined as
Mass transfer co-efficient is defined as
Ammonia present in the coke oven gas is removed by washing with
Ammonia present in the coke oven gas is removed by washing with
Mass transfer co-efficient (K) and diffusivity (D) are related according to film theory as
Mass transfer co-efficient (K) and diffusivity (D) are related according to film theory as
Pick out the correct statement.
Pick out the correct statement.
Diameter to height ratio for a rashig ring is
Diameter to height ratio for a rashig ring is
The Reynolds number of the liquid was increased 100 fold for a laminar falling film used for gas-liquid contacting. Assuming penetrating theory is applicable, the fold increase in the mass transfer co-efficient (Kc) for the same sytem is
The Reynolds number of the liquid was increased 100 fold for a laminar falling film used for gas-liquid contacting. Assuming penetrating theory is applicable, the fold increase in the mass transfer co-efficient (Kc) for the same sytem is
In case of __________ distillation, a solvent is added to alter the relative volatility of the mixture to be separated.
In case of __________ distillation, a solvent is added to alter the relative volatility of the mixture to be separated.
With increase in temperature, the rate of leaching increases, because the
With increase in temperature, the rate of leaching increases, because the
Minimum reflux ratio in a distillation column results in
Minimum reflux ratio in a distillation column results in
Absorption accompanied with chemical reaction is exemplified by the absorption of
Absorption accompanied with chemical reaction is exemplified by the absorption of
Fenske equation determines the
Fenske equation determines the
__________ is the separation technique used for desalination of sea water.
__________ is the separation technique used for desalination of sea water.
An alkaline solution is used to reduce the concentration of carbon dioxide in a stream from 10% to 0.1% by absorption with irreversible chemical reaction. The overall number of transfer units based on gas phase is
An alkaline solution is used to reduce the concentration of carbon dioxide in a stream from 10% to 0.1% by absorption with irreversible chemical reaction. The overall number of transfer units based on gas phase is
In the constant rate period of the rate of drying curve for batch drying,
In the constant rate period of the rate of drying curve for batch drying,
Steady state equimolal counter diffusion is encountered in
Steady state equimolal counter diffusion is encountered in
Stage efficiency in a leaching process depends on the
Stage efficiency in a leaching process depends on the
Sticky material can be dried in a __________ dryer.
Sticky material can be dried in a __________ dryer.
Sand is dried in foundaries in a___drier.
Sand is dried in foundaries in a___drier.
According to the Fenske equation, what will be the minimum number of plates required in a distillation column to separate an equimolar binary mixture of components A and B into an overhead fraction containing 99 mol% A and a bottom fraction containing 98 mol% B? Assume that relative volatility (αAB = 2) does not change appreciably in the coloumn.
According to the Fenske equation, what will be the minimum number of plates required in a distillation column to separate an equimolar binary mixture of components A and B into an overhead fraction containing 99 mol% A and a bottom fraction containing 98 mol% B? Assume that relative volatility (αAB = 2) does not change appreciably in the coloumn.
Which of the following liquid-vapor contacting devices provides maximum contact surface area for a particular duty?
Which of the following liquid-vapor contacting devices provides maximum contact surface area for a particular duty?
During the constant rate period of drying of a solid,
During the constant rate period of drying of a solid,
In a distillation operation, what is the effect of the temperature of the reflux stream (given below) on the condenser and reboiler loads? Reflux conditions:
(i) Reflux stream is completely liquid and is at its bubble point.
(ii) Reflux stream is below its bubble point.
In a distillation operation, what is the effect of the temperature of the reflux stream (given below) on the condenser and reboiler loads? Reflux conditions:
(i) Reflux stream is completely liquid and is at its bubble point.
(ii) Reflux stream is below its bubble point.
The suitable evaporator for concentration of foaming liquids is a __________ evaporator.
The suitable evaporator for concentration of foaming liquids is a __________ evaporator.
The solvent used in liquid-liquid extraction should have __________ less than one.
The solvent used in liquid-liquid extraction should have __________ less than one.
Stefan's law describes the mass transfer by
Stefan's law describes the mass transfer by
Mass transfer co-efficient is directly proportional to DAB according to the __________ theory.
Mass transfer co-efficient is directly proportional to DAB according to the __________ theory.
