Month: February 2019

The mass transfer co-efficient for a solid sphere of radius ‘a’ dissolving in a large volume of quiescent liquid, in which „D’ is the diffusivity of solute, is _____________________?

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The mass transfer co-efficient for a solid sphere of radius ‘a’ dissolving in a large volume of quiescent liquid, in which „D’ is the diffusivity of solute, is _____________________?

A. D/a
B. D/2a
C. Proportional to √D
D. Dependent on the Reynolds number

Experiments were conducted to determine the flux of a species A in a stagnant medium across a gas-liquid interface. The overall mass transfer co-efficient based on the liquid side for dilute systems for the above was estimated to be 4 × 10-3 kg mole/m2.s. The equilibrium data for the system is given as y = 2x. The flux across the interface (in kg mole/m2 .s) for bulk concentrations of A in gas phase and liquid phase as y = 0.4 and x = 0.01 respectively is _________________________?

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Experiments were conducted to determine the flux of a species A in a stagnant medium across a gas-liquid interface. The overall mass transfer co-efficient based on the liquid side for dilute systems for the above was estimated to be 4 × 10-3 kg mole/m2.s. The equilibrium data for the system is given as y = 2x. The flux across the interface (in kg mole/m2 .s) for bulk concentrations of A in gas phase and liquid phase as y = 0.4 and x = 0.01 respectively is _________________________?

A. 5.6 × 10-4
B. 8.5 × 10-4
C. 5.6 × 10-3
D. 8.5 × 10-3

H2S is being absorbed in a gas absorber unit. The height of the transfer unit based on the overall mass transfer coefficient on the gas side is 0.4 m. The equilibrium data is given by, y = 1.5 x. The bulk concentration of H2S has to be reduced from 0.05 to 0.001 mole fraction in the gas side. The height of the tower (in meters) corresponding to an operating line given by, y = 5x + 0.001 is ______________________?

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H2S is being absorbed in a gas absorber unit. The height of the transfer unit based on the overall mass transfer coefficient on the gas side is 0.4 m. The equilibrium data is given by, y = 1.5 x. The bulk concentration of H2S has to be reduced from 0.05 to 0.001 mole fraction in the gas side. The height of the tower (in meters) corresponding to an operating line given by, y = 5x + 0.001 is ______________________?

A. 2.0
B. 1.56
C. 1.0
D. 0.56