 Occurs when both atoms have low ionization energies and low electronegativities → will lose electrons easily

 Metallic bonding is the strong attraction between closely packed positive metal ions and a 'sea' of delocalised electrons.

 Since the electrons are delocalized (don’t belong to any one atom), they are mobile and able to move throughout the metal structure

 Metals are solids at room temperature (except Hg) due to the strong bonds (intermolecular and intramolecular forces are the same)  Metallic bonds are strong and a lot of energy is needed to break them. This is why metals have high melting points and boiling points.

 Metals contain electrons that are free to move in the metal structure, carrying charge from place to place and allowing metals to conduct electricity well.

 They exhibit the photoelectric effect which is electron emission caused by heat or light. This occurs when the frequency and therefore the energy of light striking a metal is sufficient to overcome the attractive forces and an electron escapes the metal decreasing the energy of the photon

 Malleable and ductile because atoms are not restricted to one position by a fixed bond and the ions can roll past each other  Shiny because when light strikes a metal, the valence electrons absorb energy, oscillate at the same frequency as the incident light (incoming light) & then emit the light as a reflection of the original light

 At low temperatures, some metals can become superconductors. They will have little or no electrical resistance. For example, mercury is a liquid metal. It solidifies at –38.8 °C and becomes a superconductor at –268.8 °C.  Superconductors have potential benefits, including:  Power transmission without losses  Super-fast electronic circuits  Powerful electromagnets  Superconducting electromagnets are used in hospital MRI scanners for example.