2.5. Mass Transfer Resistance

Try these first

1. 1.

   What does the term mass transfer resistance refer to?

   Hint

   Think about obstacles to mass movement.

2. 2.

   Define the concentration gradient.

   Hint

   What drives the mass transfer?

3. 3.

   What is mass transfer resistance mainly attributed to?

   • Temperature changes
   • Fluid characteristics
   • Pressure differences

   Hint

   Think about what properties affect flow.

4. 4.

   True or False: An increased boundary layer thickness decreases mass transfer efficiency.

   • True
   • False

   Hint

   What happens when spaces are filled?

5. 5.

   You have a container with air over a water surface. If an oil slick surfaces and spreads, how does this affect the mass transfer resistance in terms of both convection and diffusion?

   Hint

   Consider how each layer (air, oil, water) interacts.

6. 6.

   In an experiment, increasing the flow velocity of water increases the mass transfer coefficient while also increasing the boundary layer thickness. Explain this contradictory situation.

   Hint

   Think about how flows interact and create layers.