Illustrate by taking examples of transition elements and non-transition elements that oxidation states of elements are largely based on electronic configuration.
Ti has an atomic number off 22 and electronic configuration [Ar]3d24s2 and can show three oxidation states of +2,+3 and +4 in various compounds like TiO29(+4), Ti2O3(+3) and TiO(+2). The non transition elements like the p block elements show variable oxidation states like in case of phosphorous. It has -3,+3 and +5. Lower oxidation states are ionic in nature as they accept electrons and higher oxidation states by unpairing the electrons and shifting to d orbitals.