A. cm2/sec gm . mole
B. gm moles/cm2 . sec
C. gm moles/cm. sec
D. gm moles/cm2. sec
Related Mcqs:
- The mass diffusivity, the thermal diffusivity and the eddy momentum diffusivity are same for, NPr = NSc = _________________?
A. 1
B. 0.5
C. 10
D. 0 - If mass diffusivity in a mixture is equal to the thermal diffusivity, then the Lewis number is____________________
A. 0
B. 1
C. 1 - In case of non-ideal gases and liquids, the molal diffusivity ________________?
A. Varies inversely as the pressure
B. Varies directly as the pressure
C. Is independent of pressure
D. Is equal to the volumetric diffusivity - The diffusivity, DAB (for component A diffusing in B) is equal to the diffusivity DBA (for component B diffusing in A) for a binary mixture of________________?
A. Newtonian liquids
B. Non-Newtonian liquids
C. Ideal gases
D. Real gases - Which of the following assumes constant molal vaporisation and overflow ?
A. McCabe-Thiele method
B. Ponchan-Savarit method
C. Enthalpy concentration method
D. Plate absorption column - If xD = overhead product molal composition and RD = reflux ratio, then slope and intercept of the operating line for rectifying section are respectively ?
A. [xD/(RD + 1)], [RD/(RD + 1)]
B. [RD/(RD + 1)], [xD/(xD + 1)]
C. [xD/(RD + 1)], [(RD + 1)/RD]
D. None of these - Penetration theory relates the average mass transfer co-efficient (K) with diffusivity D. as____________________?
A. K ∝D
B. K ∝√D
C. K ∝D1.5
D. K ∝D2 - As per Gilliland’s equation, the diffusivity is___________________?
A. Directly proportional to ‘T1.5’
B. Inversely proportional to ‘P’
C. Dependent on the molecular volume & molecular weight of components
D. All A , B. & C. - Liquid diffusivity is of the order of _______________ cm2 /second?
A. 0.01
B. 0.1
C. 10-5 to 10-6
D. > 1 - Diffusivity in concentrated solutions differs from that in dilute solutions, because of the changes in ____________________?
A. Viscosity with concentration
B. Degree of ideality of the solution
C. Both A. and B.
D. Neither A. nor B.
