Molecular Solids: Definition and Examples

They tend to dissolve in organic solvents

A Spoonful of Sugar
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A molecular solid is a type of solid in which molecules are held together by van der Waals forces rather than by ionic or covalent bonds.

Properties of Molecular Solids

The dipole forces are weaker than ionic or covalent bonds. The relatively weak intermolecular forces cause molecular solids to have relatively low melting points, typically less than 300° C. Molecular solids tend to dissolve in organic solvents. Most molecular solids are relatively soft electrical insulators with low density.

Examples of Molecular Solids

  • Water ice
  • Solid carbon dioxide
  • Sucrose, or table sugar
  • Hydrocarbons
  • Fullerenes
  • Sulfur
  • White phosphorus
  • Yellow arsenic
  • Solid halogens
  • Halogen compound with hydrogen (e.g., HCl)
  • Pnictogens (N2)
  • Light chalcogens (O2)