Question

  Explain van der Waals forces in your own words. As part of your explanation, explain the relative strength (highest, lowest, middle) of the van der Waals forces in the following three molecules: diatomic hydrogen, H₂; ethanol, CH₃COOH; carbon tetrachloride, CCl₄.

Answer 1

Vander waal forces are short distance acting forces, which are attractive or repulsive that act between molecules.

The vanderwaal forces present in each of the given molecules:

The relative strength of vanderwaal forces is Hydrogen bonding > dipole interactions > induced dipole-induced dipole interactions.

Hydrogen : Induced dipole - induced dipole interactions (Lowest)

Ethanol : Dipole-dipole interactions along with hydrogen bonding. (Highest)

Carbon tetrachloride: Dipole-dipole interactions (Middle)