At equilibrium the concentration of water in vapour phase (C*)in kg/m3 of air space and the amount of water (m) adsorbed per kg of dry silica gel are related by, C* = 0.0667m. To maintain dry conditions in a room of air space 100m3 containing 2.2 kg of water vapour initially, 10 kg of dry silica gel is kept in the room. The fraction of initial water remaining in the air space after a long time (during which the temperature is maintained constant) is
Dry bulb temperature of unsaturated air is more than its __________ temperature.
For the case of flow of air past a wet bulb thermometer (air water vapour system), the approximate value of h2/ky.Cz is around
The reciprocal of stripping factor is termed as
Ponchan-Savarit method analyses the fractional equipment based on
The binary diffusivity in gases at atmospheric conditions is about
Percentage saturation is __________ the relative saturation.
In case of a desorber (stripper), the
What is the reflux ratio at total reflux ?
Under conditions of flooding in packed tower, the gas pressure drop
For achieving rapid drying rate in a spray dryer, the diameter of the particles in the feed should be in the range of __________ microns (1 mm = 1000 microns).
For absorbing a sparingly soluble gas in a liquid
The minimum number of theoretical plates is required for achieving a given separation in distillation column with
Channelling in a packed tower results from the
The change in enthalpy per unit weight of adsorbed gas when adsorbed on gas free or "outgassed" adsorbent to from a definite concentration of adsorbate is called its
A good solvent used for absorption should not have very high
In a counter-current liquid extractor
Which of the following is an undesirable property for an absorbing solvent ?
The wetted wall tower is used to determine
For a ternary mixture, the number of cuts required is_________
The first two high volatile components are stored in two cuts and the low volatile remains in the still itself.
With increase in gas rate, the number of transfer units, NtoG, for a fixed degree of absorption by a fixed amount of solvent
Schmidt number is given by
Positive deviation from Raoult's law means a mixture whose total pressure is
The caking of crystals can be prevented by
Prandtl number for water at 20oC is about