Electronic Theory Of Valency: In 1916, Kossel and Lewis put forward a new concept of valency on the basis of the structure of an atom. According to this theory- The valency of an element depends upon the number of electrons in the outermost shell. These electrons are referred to as valence electrons. The noble gases possess a stable electronic configuration in their atomic structure. Thus, the valence electrons in the outermost shell of inert gases (i.e. 2 for He and 8 for the rest of the elements) form a stable structure. This electronic configuration is regarded as a configuration of … Continue reading Electronic Theory Of Valency