covalent compounds

• types of substance made out of COVALENT bonds:

  1. SIMPLE MOLECULAR SUBSTANCES

  2. GIANT COVALENT SUBSTANCES

  3. POLYMERS
• Simple Molecular Substances (Small Molecules)

  consist of SMALL MOLECULES formed by COVALENT BONDS and are not large networks but small groups of atoms bonded together.

  • e.g. Hydrogen (H₂), Oxygen (O₂), Water (H₂O) and Chlorine (Cl₂).
• Properties of Simple Molecular Substances

  INTERMOLECULAR FORCES: the forces BETWEEN MOLECULES which are weak and do NOT need a lot of energy to overcome.

  
• Properties of Simple Molecular Substances


  COVALENT BONDS: the bonds BETWEEN ATOMS which are STRONG and need A LOT of energy to overcome.

  
• Melting and Boiling Points:

  When simple molecular substances MELT or BOIL, it's the intermolecular FORCES that need to be broken, NOT the covalent bonds and the forces are WEAK, meaning a SMALL amount of energy is needed to break them.

  • this gives simple molecular substances LOW melting and boiling points and is why they are found as LIQUIDS or GASES at room temperature.