Question

Oxygen generally exhibits an oxidation state of – 2, whereas the other members of its family show oxidation states of +2, +4 and +6 as well. Explain.

Answer 1

• The electronic configuration of oxygen is ls²2s²2p⁴. 
• It has two half filled p-orbitals and no d-orbitals for excitation of electrons. Hence it cannot show higher oxidation states. 
• Oxygen being highly electronegative, it mostly shows an oxidation state of – 2 only. 
• Other members of the family like sulphur, have vacant d-orbitals, thereby giving four and six halffilled orbitals for bonding. 
• Furthermore, they can combine with more electronegative elements. 
• Hence, they show oxidation states of +2, +4 and 4 -6 also.