Metallic character of Transition element

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Metallic character:

 Transition elements can lose one or two (ns¹  or ns²) electrons and are changed to positive cations. Hence, they are metals. They are solid ( except Hg which is a liquid at room temperature), hard, lustrous, malleable , ductile and good conductor of heat as well as electricity and they possess high tensile power or strength.

    This is due to the fact that transition metal atom have one or two electron in their outermost shell (ns¹-²), and their ionization enthalpies are relatively low , for which they can form metallic bond. The unpaired d - electrons also cause the Formation of metallic bonds . It is a fact that greater the number of unpaired d-electron , stronger is the metallic bonding due to the overlap of unpaired electron between different atoms .
Since Cr , Mo and W have maximum number of unpaired d-electron (=5) , they are hard metals ; Zn , Cd and Hg are soft metals having low melting point because of having no unpaired d-electron. Hg is a liquid due to the absence of unpaired d-electron.

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