Question -
Answer -
The elements of group 16 arecollectively called chalcogens.
(i) Elementsof group 16 have six valence electrons each. The general electronicconfiguration of these elements is ns2 np4,where n varies from 2 to 6.
(ii) Oxidation state:
As these elements have sixvalence electrons (ns2 np4), theyshould display an oxidation state of −2. However, only oxygen predominantlyshows the oxidation state of −2 owing to its high electronegativity. It alsoexhibits the oxidation state of −1 (H2O2), zero (O2),and +2 (OF2). However, the stability of the −2 oxidation statedecreases on moving down a group due to a decrease in the electronegativity ofthe elements. The heavier elements of the group show an oxidation state of +2,+4, and +6 due to the availability of d-orbitals.
(iii) Formation ofhydrides:
These elements form hydrides offormula H2E, where E = O, S, Se, Te, PO. Oxygen andsulphur also form hydrides of type H2E2. These hydridesare quite volatile in nature.