siirtometallien

Siirtometallit, also known as transition metals, are a group of chemical elements found in the d-block of the periodic table. They are characterized by having incompletely filled d electron shells, either in their elemental form or in their common ions. This electron configuration gives rise to many of their unique chemical properties.

The transition metals include elements from Group 3 to Group 12 of the periodic table. They exhibit variable oxidation states, meaning they can lose different numbers of electrons to form ions with varying charges. This property is a key reason for their diverse chemical behavior. Many transition metal compounds are colored, a phenomenon often related to the electronic transitions within the d orbitals.

Transition metals are also known for their catalytic activity. Their ability to readily change oxidation states and form intermediate complexes makes them highly effective catalysts in numerous industrial processes, such as the Haber-Bosch process for ammonia synthesis and the catalytic converters in vehicles. Furthermore, these elements often form complex ions, where a central metal atom or ion is bonded to surrounding molecules or ions called ligands.

In terms of physical properties, transition metals are typically hard, dense, and have high melting and boiling points. They are good conductors of heat and electricity. Many transition metals, such as iron, copper, and gold, are of significant economic importance and have widespread applications in industry, technology, and everyday life due to their strength, conductivity, and resistance to corrosion.