Metalic bonding, transition metals
anthony yates
metalic bonding
All metals have only a few electrons in the outer shells of their atoms. In a solid metal, the atoms are close together and the outer shells overlap. The outer electrons are free to move through the structure in a 'sea of electrons'. The electrons are not located in specific atoms, so they are called delocalised electrons. The metal atoms form positive ions, which are held together in a regular arrangement.
The delocalised electrons move around randomly between the positive ions in all directions. If a potential difference is apllied across a piece of metal. the electrons start to move in one direction. This is called an electric current.
The layers of positive ions in a metal can slide over each other if a large force is applied to a piece of metal. The ions are still held together by the sea of electrons, so the metal spreads out instead of breaking. It is malleable.
Transition metals
Transition metals
Most metals are transition metals. These are in the central block of the periodic table. Most transition metals have high melting points and form coloured compounds.