This section covers metallic bonding as attraction between positive metal ions and delocalised electrons in a giant lattice.
A giant metallic lattice
Metal atoms form giant metallic lattices. Their outer-shell electrons become delocalised, so they are no longer associated with one particular atom and can move throughout the structure.
The loss of these outer electrons from the metal atoms leaves a regular arrangement of positive metal ions.
Metallic bonding is the electrostatic attraction between the positive metal ions and the delocalised electrons.
Positive metal ions occupy positions in a lattice.
Delocalised electrons move throughout the structure.
The attraction between the positive ions and negative electrons acts throughout the lattice.
The metal ions are often closely packed in hexagonal layers or a cubic arrangement.
The structure is described as a giant metallic lattice.
positive metal ions + delocalised electrons → metallic bonding
A two-dimensional representation of a giant metallic lattice.
Exam Tip: When drawing metallic bonding, include and label both the positive metal ions and the delocalised electrons. Do not draw neutral metal atoms as the particles in the lattice.