Question

1. What is meany by shell and sub shell ?

Answer 1

Shells are the circular paths around the nucleus of an atom along which the electrons traverse. (According to Bohr Model). The shells are represented by principal quantum number , n.

n=1 means the first shell or orbit and so on.

Sub-shells :

Each shell consists of one or more sub-shells. There are four sub-shells - s , p , d ,f .

For example, the first shell consists of only one sub-shell that is s.

In the second shell there are two sub-shells- s and p .

In the third shell there are three sub-shells - s, p , d .

The rest of the shells consist of all four sub-shells - s , p , d , f .