Question

Why there are groups and period in the periodic table?

Answer 1

To recognise all the elements faster

Answer 2

Hi there!
Here's the answer :

In periodic table, each row is called a period. All of the elements in a period have the same number of atomic orbitals.

In periodic table, each column is called a group. The elements in each group have the same number of electrons in the outer orbital. Those outer electrons are also called valence electrons . They are the electrons involved in chemical bonds with other elements.


Due to this similarity in rows and columns, the periodic table is arranged in such way.

:)
Hope it helps