Related Questions

According to the film theory of mass transfer, the mass transfer co-efficient is proportional to (where, D = molecular diffusivity)
A D
B D2
C D0.5
D $$\frac{1}{{\text{D}}}$$
If mass diffusivity in a mixture is equal to the thermal diffusivity, then the Lewis number is
A 0
B 1
C > 1
Mass transfer co-efficient (K) and diffusivity (D) are related according to film theory as
A K ∝ D
B K ∝ $$\sqrt {\text{D}} $$
C K ∝ D1.5
D K ∝ D2
Penetration model (theory) for mass transfer was enunciated by
A Danckwerts
B Toor and Marchello
C Higbie
D Kissinevskii
The ratio of momentum diffusivity to thermal diffusivity is the __________ number.
A Prandtl
B Nusselt
C Stanton
D Grashoff
If the catalyst pore size is small in comparison with the mean free path, collisions with the pore wall controls the process'. The diffusivity under this condition is called 'Knudsen diffusivity', which is affected by the
A Pressure
B Temperature
C Both A & B
D Neither A nor B
The scales form in heat exchanges after a period of operation and provide additional resistance to heat transfer with some heat transfer coefficient . The reciprocal of this scale heat transfer coefficient is called .
A scaling factor
B forming factor
C resisting factor
D fouling factor
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 $$\sqrt {\text{D}} $$
D Dependent on the Reynolds number
The film penetration model of mass transfer was enunciated by
A Gilliland
B Toor and Marchello
C Stefan
D Fick
Three maths classes: X, Y, and Z take an algebra test. The average score of class X is 83. The average score of class Y is 76. The average score of class Z is 85. The average score of class X and Y is 79 and the average score of class Y and Z is 81. What is the average score of the combined classes X, Y, and Z?
A 81
B 81.5
C 82
D 84.5

Next steps