The middle layer present in the periodic table is filled with the d block elements. The inner d orbits of group 3 to 13 are progressively filled. On the other side, the f block elements are found outside and at the bottom of the periodic table. In these elements, the 5f and 4f orbitals are progressively filled. The 3 series of transition elements are recognised by the filling of 3d, 4d, and 5d orbitals. They hold a high boiling and melting point. The metallic properties that are exhibited by the transition elements are given as follows:
Electrical conductivity
Thermal conductivity
Malleability
Metallic character
High tensile strength
Ductility
