Transition metal

A transition metal is an element which forms at least one ion with a partially filled d subshell. The transition metals tend to inhabit the middle block of the periodic table and have many uses in modern industry.

Properties and Uses

• Strong oxidising and reducing agents - the transition metals are strong oxidising agents. This is because of the small energy gap between the (n)s and (n-1)d subshells, allowing the atom to readily lose electrons from each. This results in a number of oxidation states and a readiness to change. As such species existing with a high oxidation number will be strong oxidising agents, whereas species with a low oxidation number will be strong reducing agents. As such they are used extensively in the chemical manufacturing industry and research.

• Colour - the d subshell of a transition ion is usually degenerate (all the same energy level), however in the presence of other atoms and ligands it can split into two energy levels with an energy gap often corresponding to wavelengths of electromagnetic radiation in the visible spectrum. As such a compound with a transition metal is able to absorb wavelengths of light causing them to be redundant in the reflected ray, hence producing colour. As such transition metals form the basis of our paint and pigment industries.

See Also

• Periodic table