Shell and Subshell Simple Explanation
What is a shell in chemistry?
SHELLS
Electrons revolve around the nucleus in a particular circular pattern known as the shell of an atom.
The electron shell is also known as orbit or energy level.
Shell Representation
It is denoted by n. Where n is any positive integer.
Each shell has a fixed amount of energy.
n=1 is known as K-Shell
n=2 is known as L-Shell
n=3 is known as M-shell
Finding the maximum number of electrons in any shell Formula
The maximum number of electrons in any shell can be found by using the Bohr filling formula=2n2
What is meant by sub-shells?
SUB-SHELLS
A shell or energy level is further divided into sub-shells. A subshell is defined as ( The region where the probability of finding an electron is maximum in the orbit is termed as a subshell.) The n value of a shell is written before the symbol of a sub-shell.
EXAMPLES
- For n=1, K-shell contains only one sub-shell 1s
- For n=2, L-shell contains two sub-shells represented as 2s,2p
- For n=3, M-shell contains three sub-shells represented as 3s,3p,3d
- For n=4, N-shell contains four sub-shells represented as 4s,4p,4d,4f
Maximum electrons in a subshell
- S subshell can accommodate a maximum of 2 electrons
- P subshell can accommodate a maximum of 6 electrons
- D subshell can accommodate a maximum of 10 electrons
- F subshell can accommodate a maximum of 14 electrons
Distinguish between shell and subshell
| Shell (Energy level or Orbit) | Sub-shell (Sub-Energy level) |
| The circular path that electrons take around the nucleus is known as their shell or orbit. | A shell or energy level is further subdivided into subshells or sub-energy levels. |
| Each shell is specified (represent) by n value n = 1,2,3,4,5,………………. | Each sub-shell is specified by the l value. L = 0,1,2,3,4, ….. |
| N= 1 ( K shell) N=2 (L shell) N= 3 (M shell) N=4 (N shell) | K shell -> s subshell L shell -> s, p subshells M shell -> s, p, d subshells N shell -> s, p, d, f subshell |
| Using formula 2n2 to determine the total number of electrons in a shell. n= 1 ( K shell) 2 (1)2 = 2e– n=2 (L shell) 2 (2)2 = 8e– n= 3 (M shell) 2 (3)2 = 18e– n=4 (N shell) 2 (4)2 = 32e– | Number of sub-shells in a shell = value of “n” s = 2e– p= = 6e– d== 10e– f = 14e– |
Q.What are energy shells in chemistry?
There is a specific amount of energy tied to the energy shell. The energy associated with an orbit increases with the orbit’s separation from the nucleus. The energy level is also the name of these shells.
Q.How many subshells are there in N subshell?
The number of sub-shells within a shell = “n” value.
It indicates that there are four subshells named 4s,4p,4d, and 4f for the N shell.
Q. Provide notation for subshells of M shell?
The number of sub-shells within a shell = “n” value.
It indicates that the M shell has three subshells designated 3s, 3p, and 3d.
Q.State Aufbau principle.
AUFBAU PRINCIPLE
Named after the German phrase “Aufbau,” which means “to build up,”
According to the Aufbau principle, electrons will first occupy lower-energy orbitals before moving on to those with higher energies.
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