bonding+structure

electron(s) transferred from one atom to another

gives full outer shell electrons

• giant lattice
• strong electrostatic forces of attraction between oppositely charged ions
• lots of energy needed to break strong bonds → high melting point
• free ions when molten → can conduct electricity

• weak (van der Waals) forces between molecules → low melting point
• overall charge is neutral → no free ions → cannot conduct electricity

• covalent bonds → strong intermolecular forces →  lots of energy needed to overcome → high melting point
• no free ions → does not conduct electricity

• giant lattice
• closely packed protons
• delocalised electrons

• delocalised electrons can move through structure of metal → metal can conduct electricity
• strong attractive forces between protons and delocalised electrons → lots of energy needed to overcome them → high melting point