C2.2.4 - Properties of small molecules

• Properties of small molecules

  • Low melting points and boiling points.
  • Don't need as much Energy as there are less forces to overcome.
  • some forces of attraction are overcome during melting, allowing molecules to move over each other.
• What happens when properties of small molecules melt/boil?

  There are intermolecular forces between small molecules. Intermolecular forces are much weaker than the strong covalent bonds in molecules. When small molecular substances melt or boil, it is these weak intermolecular forces that are overcome. The covalent bonds are not broken. Relatively little energy is needed to overcome the intermolecular forces, so small molecular substances have low melting and boiling points.