Describe metallic bonding as attraction between positive ions and delocalised electrons.

Metallic bonding is defined as the attraction between positive metal ions and delocalised electrons. In a metallic lattice, metal atoms lose their outer electrons, which become delocalised and free to move throughout the structure. This creates a sea of electrons that hold the positively charged ions together through electrostatic forces. The delocalised electrons allow metals to conduct electricity and heat efficiently, as they can move freely in response to an electric field or thermal gradient. Additionally, this bonding structure contributes to the malleability and ductility of metals, enabling them to be shaped without breaking.