Justify the placement of O, S, Se, Te and Po in the same group of the periodic table in terms of electronic configuration, oxidation states and hydride formation.

Explanation

The members of the oxygen family are placed in group 16 of p-block. Their inclusion in the same group is justified on the basis of following characteristics.
1. Electronic configuration. Members of the family has `ns^(2)p^(4)` configuration. Their group (10+6) is 16.
2. Oxidation states. With exception of oxygen which exhibits -2 oxidation state in its compounds `(OF_(2) " and " H_(2)O_(2)` are exceptions), rest of the members of the family show varible oxidation states `(-2, +2, +4, +6)` in their compounds.
3. Hydride formation. All the members of the family form covalent hydrides `(MH_(2))` in which the central atom is `sp^(3)` hybridised. These have angular structures and their characteristics show regular gredation.