Question

Many atoms do not combine with hydrogen.So how do we calculate the valency with the help of chlorine?​

Answer 1

Answer:

defining valency of a certain atom of an element with respect to the number of hydrogen or chlorine atoms with which it combines ; is an old concept ,

here hydrogen and chlorine was chosen because these where the one of the most abundant elements at that time so it was easier to see the relationship of any atom of an element with respect to these two…

however, the new definition of valency do not includes hydrogen and chlorine.. why because there many compounds in which elements do not combines with hydroge and chlorine ..so for that case is it will be very difficult for us to define valency …and also by using hydrogen and chlorine as a reference point for defining valency we would have multiple as well as fractional vacancies(in case of nitrogen forming NH3,N2H2,N3H)… So this concept has been exempted and new concept of a valency is evolved by defining valency of an atom as the number of chemical bonds that it makes with other element…