6.1. Diffusion Models and Predictions

Try these first

1. 1.

   What is molecular diffusion?

   Hint

   Think about how scents spread in a room.

2. 2.

   Define advection.

   Hint

   Consider what happens in a flowing river.

3. 3.

   What primarily drives molecular diffusion?

   • Temperature
   • Concentration gradient
   • Fluid velocity

   Hint

   Think about how smells spread in different areas.

4. 4.

   True or False: Advection can occur without a fluid.

   • True
   • False

   Hint

   Consider what advection means in terms of movement.

5. 5.

   Design a scenario where you have to model the transport of a pollutant in a lake with significant stratification. Discuss the roles of diffusion and advection during different seasons.

   Hint

   Consider temperature profiles and seasonal changes.

6. 6.

   Evaluate the movement of a non-water-soluble pollutant in groundwater. Discuss the factors affecting its diffusion and what mechanisms may also play a role.

   Hint

   Think about how different soil types can influence flow and diffusion.