Question

Taking the example of an element of atomic number 16, explain how the electronic configuration of the atom of an element relates to its position in the modern periodic table and how valency of an element is calculated on the basis of its atomic number.

Answer 1

Atomic number of the element =16

Electronic configuration = 2, 8, 6 Period number = Number of shells it

The atom of the element has three shells. So, the period number is 3.

The atom of the element has six valence electrons. So, the group number of the element will be 16 (6 + 10).

Valency = 8 - number of valence electrons (> 5) or number of valence electrons (<5)

Answer 2

electronic configuration = 2,8,6

there are 3 shells therefore belong to period 3

valence electron = 6

valency = 8-6

             =2