Chemical Engineering - MCQ Practice Questions

In a binary diffusion process, the mass transfer coefficient 'k_c' has dimensions of:

Which of the following best describes the Schmidt number (Sc) in mass transfer?

For a spherical particle undergoing mass transfer, the Sherwood number correlation for creeping flow (Re << 1) is approximately:

In liquid-liquid extraction, the distribution coefficient K_D is defined as the ratio of solute concentration in:

The Fick's first law of diffusion in binary mixtures states that the molar flux J_A is proportional to:

For equimolar counter-diffusion in a binary system, the molar fluxes satisfy:

The Stefan problem in mass transfer involves:

In a countercurrent absorption column, if the gas-phase mass transfer coefficient is k_G = 0.05 kmol/(m²·s·atm), the interfacial area 'a' = 200 m²/m³, and column cross-section = 5 m², the volumetric overall mass transfer coefficient is:

The penetration theory for mass transfer assumes that the contact time between fluid elements is:

For absorption of a sparingly soluble gas in a liquid with fast reaction kinetics, the enhancement factor 'E' is determined by:

In membrane separation, the permeate flux in reverse osmosis is given by:

A gas A diffuses through a stagnant film of gas B. If the diffusivity D_AB = 0.1 cm²/s, film thickness δ = 0.01 cm, and concentration difference = 0.05 mol/cm³, the diffusive flux is:

The height of a transfer unit (HTU) in a packed absorption column represents:

In foam fractionation for protein separation, the enrichment factor depends on:

For a non-isothermal diffusion process with coupled heat and mass transfer, the Lewis number Le is defined as:

The asymptotic solutions for mass transfer in turbulent flow predict that the Sherwood number varies with Reynolds number as:

In gas-solid adsorption, the Langmuir isotherm assumes:

For simultaneous diffusion and reaction (fast reaction regime) in a porous catalyst, the effectiveness factor η approaches:

In hollow fiber membrane contactors for gas absorption, the advantage over conventional columns is:

The correlation for mass transfer coefficient in agitated vessels (Harriott equation) is k_L·a ∝: