4.3. Controlling Resistance and Analogies

Try these first

1. 1.

   What is meant by mass transfer resistance?

   Hint

   Think about physical barriers in a system.

2. 2.

   Define mass transfer coefficient.

   Hint

   It has a key role in flux calculations.

3. 3.

   What does mass transfer resistance refer to?

   • Barriers to mass transfer
   • A type of mass coefficient
   • Phase stability

   Hint

   Think about what slows down the transfer.

4. 4.

   True or False: Resistance in series indicates individual resistances are multiplied to find the overall resistance.

   • True
   • False

   Hint

   Remember how electric circuit resistances work.

5. 5.

   Given a mass transfer coefficient k1 of 0.5 and k2 of 1.0, calculate the flux if the bulk concentrations are C1 = 0.2 and C2 = 0.05.

   Hint

   Examine both concentrations' contributions to total flux.

6. 6.

   If a lake has a VOC concentration of 0.3 mg/L and the ambient air shows 0.02 mg/L, apply Henry's law to find the equilibrium concentration.

   Hint

   The focus is on understanding what values are needed for kH.