Tiêu đề 8.THE d- AND f-BLOCK ELEMENTS.pdf ✅

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https://www.chemcontent.com/ 3 THE d- AND f-BLOCK ELEMENTS Introduction to d-block elements • In the periodic table the d block consist of the elements of group 3 to 12. • The d orbital of the d-block elements in four periods are filled. • The three series of the transitionmetals are 3d series from Sc to Zn, 4d series from Y to Cd and 5dseries from La • to Hg. • The fourth 6dseries begins from Ac and is incomplete till now. Position of d-block in periodic table
https://www.chemcontent.com/ 4 • The d-block elements are found in the middle section of s- and p- block elements in the periodic elements. • This lead to its name ‘transition’ due to its position between s- and p- block elements. Electronic Configurations of the d-Block Elements • The electronic configuration of d-block elements is(n-1) d1–10 ns1–2 . They have two incomplete outershells. • Where (n–1) = Inner d orbitals having electrons from 1-10. • ns = Outermost orbital may have one or two • (n-1) d10 n s2 represents the electronic configurations of Zn, Cd and Hg. • They exhibit variable valency that differ by units of one.