Illustrate by taking examples of transition elements and non-transition elements that oxidation states of elements are largely based on electronic configuration.

Explanation

Oxidation state of an element is the charge (+ ve or - ve) with an atom of the element has on its ion or appears to have when present in the combined state with other atoms. The actual sign and exact value of oxidation state on an element however depends upon its electronic configuration . For non- transition (representation element ) , the value of the oxidation state is equal to the number of electrons present in the outermost shell or eight minus the number of electrons present in the outermost shells (valence shell ) . For example s- block element have either one (alkali metals ) or two (alkaline earth metals) electrons in the outermost shell which they can lose very easily to acquire the stable electronic configuration of the nearest noble gas and hence show oxidation states of either + 1 ( alkali metals ) or + 2 (alkaline earth metals). p-Block elements on the other hand show positive negative and even zero oxidation states. For example acquire group 13 element (i.e., B , A1 etc ) . have three electrons in the outermost shell which they can lose easily to acquire stable electronic configuration of the nearest noble gas and hence show a maximum oxidation state of + 3 . Elements of group 14 (i.e., C, Si ) neither have a strong tendency to lose or gain four electrons and hence show a maximu oxidation state of + 4 or minimum of -4 group 15 elements (i.e., N, P , etc ) have a somewhat more tendency to gain three electron than to five electrons and hence show a minimum oxidation state of -3 or maximum of + 5 . Group 16 elements (i.e., O, S, etc ) have even more tendency to gain two electrons than to lose six electrons and hence show a minimu oxidation state of -2 or maximum of +6 Group 17 elements (i.e., halogens , F, C1 etc ) have the highest tendency to gain one than of lose seven electrons and hence show a minimum oxidation state of -1 or maximum of + 7 . The story of group 18 elements (i.e., noble gases ) is however quite different . They have their respective valence shells complete (He has two , all other have eight electrons) and hence show no tendecy to lose or gain electrons. Therefore in general , they show an oxidation state of zero. for example helium, neon and argon do not at all enter into chemical combination and hence always show an oxidation state of zero . However there are some exceptions . For example krypton shows some tendency to enter into chemical combination and shows a maximum oxidation states of + 8 since it has eight electrons in the valence shell.
Like some p- block elements, transition elements ( d- block) and inner transition element (f - block ) also show variable oxidation states. But unlike p- block elements, the variable oxidation states of transition and inner transition elements arise due to involvement of not only hte valence electrons but d- or f- electrons as well. However their most common oxidation states are + 2 and + 3.