5.3 Covalent bonding

• A covalent bond is the electrostatic attraction between the shared pair of electrons and the nuclei of the atoms
• Many covalent compounds exist as simple molecules
• Covalent bonds can be represented in dot-and-cross diagrams
• Multiple covalent bonds can be formed between the same atoms in a molecule
• Dative covalent bonds are lone pairs of electrons from one atom shared with another
• Lone pairs of electrons are paired electrons that are not involved in bonding
• Dative covalent bonds are often shown in displayed formulae by an arrow
• Some molecules form an outer shell with less than eight electrons, such as Boron
• Some molecules form outer shells with more than eight electrons, such as Sulphur
• Average bond enthalpy is a measurement of covalent bond strength