Electron configuration for Lithium via Bohr model (Orbit)
Bohr model describes the visual representation of orbiting electrons around the small nucleus. It used different electron shells such as K, L, M, N…so on.
These electron shells hold a specific number of electrons that can be calculated via the 2n2 formula where n represents the shell number.
|Electron shells||Shell number (n)||Max. number of electrons (2n2)|
So, K is the first shell or orbit that can hold up to 2 electrons, L is the 2nd shell which can hold up to 8 electrons, M is the third shell that can hold up to 18 electrons, and N is the fourth shell that can hold up to 32 electrons.
Now, Lithium has an atomic number of 3 and it contains a total number of 3 electrons. Hence, 2 electrons will go into the first shell(K), and the remaining electron will go into the second shell(L).
Therefore, the electrons per shell for Lithium is 2, 1, hence, we can say, based on the shell, the electronic configuration of the Lithium atom is [2, 1].
Lithium (Li) Electron Configuration
The orbital diagram simply represents the arrangement of electrons in the different orbitals of an atom, it uses an arrow to represent the electrons, every orbital(one box) contains a maximum of 2 electrons.
There are three rules followed for constructing the orbital diagram for an atom.
(1). Aufbau’s principle:- This rule state that the lower energy orbital will be filled before the higher energy orbital, for example – the 1s orbital will fill before the 2s orbital.
(2). Hund’s rule:- This rule state that each orbital of a given subshell should be filled with one electron each before pairing them. That means “Each orbital gets one electron first, before adding the second electron to the orbital”.
(3). Pauli Exclusion Principle:- This rule state that, no two electrons can occupy the same orbital with the same spin. That means “One must be spin up (↑) and one must be spin down (↓)”.
If you understand the above rules then constructing the orbital diagram or orbital notation for Lithium is super easy.
Basics of Orbital diagram:-
There are different types of orbitals – s, p, d, and, f. These orbitals contain a number of boxes that can hold a number of electrons. Let’s see.
Each box will hold a maximum of 2 electrons with opposite spin.
The orbital diagram will also be filled with the same order as described by the Aufbau principle. (1s < 2s < 2p < 3s……and so on.)
Lithium Valence electrons
Valence electrons are the outermost electrons present in the outermost shell of an atom. They have more energy, hence, they are part of most chemical reactions.
We can find valence electrons of an atom either by knowing its periodic group number or its electron configuration. Both these ways are super easy.
Which element has the electron configuration of 1s 2 2s 2 2p 6 3s 2 3p 4?
What is Li electron?