# Question #04b31

Oct 28, 2015

$S h e l l \implies S u b s h e l l \implies O r b i t a l$

#### Explanation:

Shell is the energy level of an atom ($n = 1 , 2 , 3 , e t c .$). Inside every shell there is one or more subshells ($s , p , d , f , e t c .$). Inside every subshell there is one or more orbitals .

The best way to explain this is using the quantum numbers:

where,
$n$: principal quantum number
$l$: Angular momentum quantum number

The $s$ subshell contains 1 orbital.
The $p$ subshell contains 3 orbitals.
The $d$ subshell contains 5 orbitals.
The $f$ subshell contains 7 orbitals.