5.2. Molecular Weight Considerations

Try these first

1. 1.

   Define molecular weight.

   Hint

   Think about how weights are expressed in terms of a mole.

2. 2.

   What is a mass transfer coefficient?

   Hint

   Consider how it connects to concentrations.

3. 3.

   What factor does molecular weight primarily affect in environmental processes?

   • Evaporation rate
   • Temperature
   • Pressure

   Hint

   Consider how the mass of a molecule impacts its vaporization.

4. 4.

   True or False: Heavier substances tend to evaporate faster than lighter substances.

   • True
   • False

   Hint

   Think about how energy requirements vary with molecular weight.

5. 5.

   You need to analyze the evaporation rates of two chemicals, ethylene glycol (molecular weight 62) and benzene (molecular weight 78). Compare their evaporation tendencies considering molecular weight and suggest appropriate correlations.

   Hint

   Consider how the relative weights function in terms of volatility.

6. 6.

   In a scenario where a dense non-aqueous phase liquid is introduced into a shallow river, discuss how one would calculate the mass transfer coefficient and the implications of molecular weight difference.

   Hint

   Think about how the environmental context changes based on the chemical properties.