Question

how we find that , what's the group and period of an element?​

Answer 1

If you are given with the atomic number of an element you can find it's period number and group number. The period number is related to the number of electron occupied shells in the element and the period number is linked to its valence electrons.

Answer 2

Answer:

Your answer is here:-

Explanation:

See the attachment.

Hope it helps you.