All the transition elements are metals. These are hard, and good conductor of heat and electricity. All these metals are malleable, ductile and form alloys with other metals. These elements occur in three types e.g., face- centered cubic (fcc), hexagonal close-packed (hcp) and body-centered cubic (bcc), structures.

The transition elements shows both covalent as well as metallic bonding amongst their atoms.

Explanation : The ionisation energies of the transition elements are not very high. The outermost shell in their atoms have many vacant, partially filled orbitals. These characteristics make these elements metallic in character. The hardness of these metals, suggests the presence of covalent bonding in these metals. The presence of unfilled d-orbitals favour covalent bonding. Metallic bonding in these metals is indicated by the conducting nature of these metals. Therefore, it appears that there exists covalent and metallic bonding in transition elements.

Solved Example 1: In human body if necessary, the plate, screw or wire used for surgery are made up of

(a) Ni

(b) Au

(c)Pt

(d) Ta

Ans: d

Solved Example 2: A hard and resistant metal (alloy) generally used in tip of nib of fountain pen is

(a) Os.lr

(b) Pt.Cr

(c) V.Fe

(d) Fe.Cr

Ans : b