Question

An element X belong to 3rd periods and group II of the periodic table state:

(a) the number of valence electrons,

(b) the valency,

(c) name of the element,

(d) whether it is a metal or a non-metal.

Answer 1

(a) Since it belongs to period 3 it has 3 shells, K, L and M. The outermost M shell will have 2 valence electrons as it is placed in group II

(b) With 2 valence electrons, its valency will be 2.

(c) Since it has electronic configuration of 2, 8, 2, its atomic number is 12 and hence X is Magnesium

(d) It is a metal.