Why d-block elements are called transition element ?

1.	Why d-block elements are called transition element ?
Answer» Elements in which the last electron enters the d-orbitals, are called d-block elements. These elements have general outer electronic configuration (n-1)d1-10 ns0-2.\xa0Zn, Cd and Hg which have general electronic configuration, (n-1) d10ns2\xa0do not show most of the properties of transition elements. d-orbitals in these elements are completely filled in the ground state as well as in their common oxidation states. Thus, on the basis of properties, all transition elements are d-block elements but on the basis of electronic configuration, all d- block elements are not transition elements.

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