Question

If the electronic configuration of an element is 2,8,2 to which period of the Modern Periodic Table does it belong?

Answer 1

An element have electronic configuration 2,8,2

It is magnesium.

It had 2 free electrons.

So,it is lie in 2 group and 3 period.

Answer 2

Answer:

1 . Since ‘X’ has three energy shells and period number of an element is equal to the number  of energy shells, X belongs to 3rd period.

2 . X has 2 valence electrons it belongs to group 12.

3.  Valency will be -2. To acquire noble gas configuration it will lose 2 electrons.