A transition metal or element is generally defined as a metal which has partially filled d orbitals in the neutral atom or in any of its usual positive oxidation states.

The first transition series extends from scandium (Sc) to copper (Cu).

Electronic Configuration of The First Transition Series

Properties (Physical and Chemical) of Transition ElementsTransition metals show unique physical and chemical properties.

1. They are all Metals.

2. They are hard, malleable, ductile and are of very high melting and boiling points. Compared with the main group metals (such as metals of group one), transition metals have higher boiling and melting point .

The reason for this is the presence of very strong metallic bonding - due to large number of valence electrons involved in it.

3. They are good conductors of electricity. This is because their electrons are very free to move about within the available vacant d orbitals.

4. They exhibit paramagnetism. This is due to the presence of unpaired electrons.

Chemical Properties

1. Variable oxidation state

Apart from scandium which forms only +3 oxidation state, transition metals show various positive oxidation states by losing electrons from both their 4s and 3d orbitals (the energy difference between these orbitals is small).

Oxidation state of +2 is formed by the loss of the two electrons of the 4s (except in Cr and Cu, where the two electrons are lost from 4s and 3d orbitals, with each orbital losing an electron.

Compounds of the metals (from Ti to Cr) in the +2 state are ionic and are strong reducing agents (they are strongly oxidized). Example, Ti2+, V2+ and Cr2+.