Mass Transfer – Multiple Choice Questions (MCQs)

1. 85. What is 'crystal growth' in crystallization?

   • A. The increase in size of existing crystal particles
   • B. The formation of new crystals
   • C. The dissolution of crystals
   • D. The separation of crystals from solution

2. 86. What is the 'diffusion layer' concept in mass transfer?

   • A. A thin layer near the interface where mass transfer occurs primarily by molecular diffusion
   • B. A layer of turbulent flow
   • C. A layer of stagnant fluid
   • D. A layer of solid material

3. 87. What is the 'two-film theory' of mass transfer?

   • A. A model that assumes resistance to mass transfer resides in two stagnant films on either side of the interface
   • B. A theory for turbulent flow
   • C. A theory for solid-state diffusion
   • D. A theory for ideal solutions

4. 88. In mass transfer, what does 'overall driving force' refer to?

   • A. The difference in concentration between the bulk phases
   • B. The concentration difference at the interface
   • C. The driving force within a single film
   • D. The resistance to mass transfer