Question

Oxygen and sulphur at atomic numbers 8 and 16 respectively belong to the same group of the periodic table.

On the basis of their electronic configuration name the group in which the elements occur.

Answer 1

Modern periodic table:

• The modern periodic table is an arrangement of all the elements known in accordance with their increasing atomic number and recurring chemical properties.
• It is a tabular display of 118 chemical elements which consists of horizontal rows called periods and vertical columns are called groups.
• All elements in a group have the same number of valence electrons, and in period elements have the same number of electron shells.

Electronic configuration:

• Electronic configuration, also called electronic structure, is the arrangement of electrons in energy levels around an atomic nucleus.
• The electron configuration of an element describes how electrons are distributed in its atomic orbitals.
• It can be written in K, L, M, and N format where the K, L, M, and N shells represent the energy shells.
• The total number of an electron in the shell is given by the formula$\text{2}{\text{n}}^{\text{2}}$, where n is the shell number.
• For the K shell maximum number of electrons that can be acquired is 2.
• For the L shell maximum number of electrons that can be acquired is 8.
• For the M shell maximum number of electrons that can be acquired is 18 and so on.

Oxygen has an electron configuration as 2,6.

Sulphur has an electron configuration as 2,8,6.

These elements have 6 electrons in their valence shell so they belong to group 6A or we can say group 16 (10+6= 16).