Which one of the following does not increase while moving down the group of the periodic table ?

Options

A. Atomic radius
B. Metallic character
C. Valence
D. Number of shell in an element

Answer

C

Explanation

All the elements of a group of the periodic table have the same number of valence electrons e.g., all the elements of group 1 have 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 electron in its atom. All the remaining three properties increase down the group.