The group 16 elements are collectively known as chalcogens.
(i) The elements of group 16 have six valence electrons each. The general electronic configuration of these elements is ns²np⁴, where n can vary from 2 to 6 respectively.

(ii) Oxidation state:
As these elements have six valence electrons, ns²np⁴, they should display an oxidation state of −2 (in order to complete their octet). However, only oxygen predominantly shows the oxidation state of −2 because of its higher electronegativity. It also exhibits the oxidation state of −1 (H₂O₂​), zero (O₂), and +2 (OF₂​). However, the stability of the −2 oxidation state decreases on moving down a group due to a decrease in the electronegativity of the elements. The heavier elements of the group show an oxidation state of +2, +4, and +6 due to the availability of d-orbitals such that there is an expansion electronic configuration.
(iii) Formation of hydrides:
The group-16 elements form hydrides with a formula H₂M, where M = O, S, Se, Te, Po. Oxygen and sulphur also form variable hydrides of the form H₂M₂​. These hydrides are quite volatile in nature and rapidly vaporise.