Classification Of Elements And Periodicity In Properties

The general electronic configuration of - block elements is . They show variable oxidation state because - electrons also take part in bond formation. They have degenerated orbitals. and -block elements in general do not show variable oxidation states.

Size or radii of onion is always larger than its neutral atom. Difference between and is larger radii and larger size of As the radii of the anion is always larger than the atomic radii of its parent atom. In an anion as electron or electrons are added to the neutral atom, the nuclear charge acts on more electrons, so that each electron is held less tightly and thereby, the electron cloud expands.