Guys, consider this: en of an element is defined in its elemental state. if we consider the element in a compound, its electro-negativity depends on the other elements that it is bonded with. for example, if it is bonded to an element that is less en than itself, electron density around it increases thus decreasing its en in that compound. if it is attached to a more en element, its electron density decreases, making it more en. this works for many phenomenon, but, does such a theory relating to difference in en of an element in its compounds exist? if so, plz give me a link. thanks.