question_answer 99)

    Which one of the following does not increase while moving down the group of the periodic table? (a) Atomic radius              (b) Metallic character     (c) Valence                         (d) Number of shells in an element

Answer:

                  (c) All the elements of a group of the periodic table have the same number of valence electrons, e.g., all the elements of group 1have one valence electron each in their atoms. All the elements of group 18 have 8 valence electrons each in their atoms, except helium which has only 2 valence electrons in its atom. All the remaining three properties increase down the group.