The dimension of diffusivity is same as that of the

The vapour pressure exerted by the moisture contained in a wet solid depends upon the

Stacked packing compared to dumped packing

During bottling of cold drinks (e.g. Pepsi), the main resistance to mass transfer for the absorption of carbon dioxide in water lies in the

An example of elutioh is

A solid material shows case hardening properties while drying. Which of the following should be controlled to control the drying process ?

For the air water system under ambient conditions, the adiabatic saturation temperature and the wet bulb temperature are nearly equal, because

In an operating distillation column, the

In case of steam distillation, the steam leaving the liquid is not completely saturated with distillate vapour, because

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.

The operating line for an absorber is curved, when plotted in terms of

In case of liquid-liquid binary diffusion, diffusivity of one constituent into another is not dependent on the

In a forced draft cooling tower, water is cooled fromto 80°F by exposure to air with a wet bulb temperature of 70°F. In this case, the

Pick out the wrong statement.

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.

Leaching of coffee from coffee beans is done by

The solvent used in liquid extraction should not have high latent heat of vaporisation, because

In case of binary distillation, increasing the reflux ratio above optimum does not result in the increase of

Corresponding to Nusselt number in heat transfer, the dimensionless group in mass transfer is the __________ number.

The equilibrium liquid composition compared to the vapor composition in case of azeotropic mixture is

The reason for preferring packed towers over plate towers in distillation practice is that the packed tower operation gives

Pick out the correct statement.

In liquid extraction, if the selectivity is unity, then

Wetted wall tower experiment determines the

If the specific heats of a gas and a vapor are 0.2KJ/Kg.°K and 1.5 KJ/Kg.°K respectively, and the humidity is 0.the humid heat in KJ/°Kg. is

Out of the following gas-liquid contacting devices, for a given set of operating conditions, gas pressure drop is the least in __________ tower.

If the path of liquid across the plate is very long as in case of large diameter tower, Murphree efficiency can be __________ percent.

When the liquid phase and vapour phase of a binary system obeys Raoult's and Dalton's law respectively, the relative volatility is the ratio of

In McCabe-Thiele method, at infinite reflux ratio

Liquid diffusivity is of the order of __________ cm² /second.

Pick out the correct statement.

Which of the following liquid-vapor contacting devices provides maximum contact surface area for a particular duty ?

Pick out the system with minimum boiling azeotrope at 1 atm.

Make up water is required in a cooling tower to replace the water lost by

Compound A is extracted from a solution of A + B into a pure solvent S. A Co-current unit is used for the liquid-liquid extraction. The inlet rate of the solution containing A ismoles of B/hr.m² and the solvent flow, rate ismoles of S/m². hr. The equilibrium data is represented by Y = 3X² , where Y is in moles of a A/moles of B and X is in moles A/moles of S. The maximum percentage extraction achieved in the unit is

The operation involved when the soluble material is largely on the surface of an insoluble solid and is merely washed off by the solvent is called

With decrease in the throughput (compared with the design capacity) for a bubble cap distillation column, its efficiency

Relative humidity is the ratio of the

__________ columns are used for liquid dispersion in a continuous gas phase.

The equipment frequently used for adiabatic humidification-cooling operation with recirculating liquid is

As the reflux ratio in a distillation coloumn is increased from the minimum, the

In distillation columns, the number of bubble caps per tray primarily depends upon the

Free flowing granular materials can be best dried in a __________ drier.

Which of the following quantities need not be fixed before starting the design of a co-current absorber ?

Raoult's law is applicable to the

In the constant rate period of the rate of drying curve for batch drying,

Plate towers are preferred to packed towers, when large temperature changes are involved, because of the reason that the

At the same gas flow rate, the pressure drop in a packed tower being irrigated with liquid __________ that in dry packed tower.

In batch distillation with constant reflux, overhead product composition __________ with time.

Total reflux in a distillation operation requires minimum