Chemical Engineering - MCQ Practice Questions

A pharmaceutical company is designing an absorption tower for NH₃ removal from air using H₂SO₄ solution. The Henry's law constant for NH₃ at 25°C is very small. What does this indicate about the system?

For turbulent flow in a pipe, the Colburn analogy for mass transfer is: j_D = (Sh)/(Re × Sc^($\frac{1}{3}$)). Which correlation best estimates j_D for smooth pipes?

For simultaneous heat and mass transfer in a wet bulb thermometer, the Lewis number (Le) is defined as Le = Sc/Pr. If Le = 1, what can be inferred?

A bioprocess company needs to calculate oxygen transfer rate in an aerated bioreactor. The volumetric mass transfer coefficient k_L·a depends on which parameters?

Which statement about the relationship between diffusivity and molar mass is correct according to kinetic theory?

For a binary diffusion process, the flux equation according to Fick's law in terms of mole fractions is given by:

For a countercurrent liquid-liquid extraction process, the Kremser equation is used. What is the minimum number of stages required if the separation factor is 2.0 and the extraction factor is 1.5?

For a dilute binary gas mixture diffusing through a stagnant layer, the diffusion coefficient D_AB can be estimated using the Chapman-Enskog theory. Which statement is correct?

For simultaneous momentum and mass transfer in a boundary layer, the Chilton-Colburn analogy relates j_D to friction factor f_D by:

For a hollow fiber membrane contactor used in gas-liquid mass transfer, the overall mass transfer coefficient K_OL is related to individual coefficients by:

For a binary gas mixture, the Stefan flow correction factor accounts for:

In ion exchange resins, the mass transfer resistance primarily occurs in:

The Colburn analogy relates dimensionless groups for mass, heat, and momentum transfer as:

For a pseudosteady-state diffusion with heterogeneous reaction, the effectiveness factor η accounts for:

The Thiele modulus (Φ) for a catalyst pellet determines whether the reaction is:

For a reverse osmosis process, the concentration polarization effect results in:

In coal gasification combustion analysis (2024-25 focus), the mass transfer of oxygen to solid particles is characterized by:

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: