How many valence electrons does lithium(Li) have?

The valence electron of lithium is one. Lithium is called alkali metal. Lithium is the element of group-1 and the symbol is ‘Li’. Lithium atoms participate in the formation of bonds through valence electrons. This article discusses in detail the valence electrons of lithium.

What are the valence electrons of lithium(Li)?

The total number of electrons in the last shell after the electron configuration of lithium is called the valence electron of lithium. The valence electron is the total number of electrons in the last orbit.

The valence electrons determine the properties of the element and participate in the formation of bonds. The third element in the periodic table is lithium. That is, the atom of the lithium element has a total of three electrons.

valence electrons of lithium
Valence Electrons of Lithium

The electron configuration of lithium shows that the last shell of lithium has a total of one electron. That is, we can easily say that the valence electron of lithium is one. There is an article on this site detailing the electron configuration of lithium, you can read it if you want.

How to determine the valence electron in lithium?

Now we will know how to easily determine the valence electron of lithium. The valence electron has to be determined by following a few steps. The electron configuration is one of them. It is not possible to determine the valence electron without electron configuration.

Knowing the electron configuration in the right way, it is very easy to determine the valence electrons of all the elements. There is an article published on this site detailing the electron configuration, you can read it if you want. However, this article briefly discusses electron configuration.

Scientist  Niels Bohr was the first to give an idea of the atom’s orbit. He provided a model of the atom in 1913. The complete idea of the orbit is given there. The electrons of the atom revolve around the nucleus in a certain circular path. These circular paths are called orbit( shell). These orbits(shell) are expressed by n. [ n = 1,2 3 4 . . .]

K is the name of the first orbit(shell), L is the second, M is the third, N is the name of the fourth orbit(shell). The electron holding capacity of each orbit is 2n2.

Now,

  • n = 1 for K orbit. The electron holding capacity of K orbit is 2n2 = 2 × 12 = 2 electrons.
  • For L orbit, n = 2. The electron holding capacity of the L orbit is 2n2 = 2 × 22 = 8 electrons.
  • n=3 for M orbit. The maximum electron holding capacity in M orbit is 2n2 = 2 × 3= 18 electrons.
  • n=4 for N orbit. The maximum electron holding capacity in N orbit is 2n2 = 2 × 42 = 32 electrons.
electron configuration
Electron Configuration

In addition to this method, electron configuration can be done through sub-orbits. However, valence electrons can be easily identified by arranging electrons according to Bohr principle. Now we will learn how to determine the valence electron of lithium.

Step-1: Determining the total number of electrons

First we need to know the total number of electrons in the lithium atom. To know the number of electrons, you need to know the number of protons in lithium. And to know the number of protons, you need to know the atomic number of the lithium element.

To know the atomic number we need to take the help of a periodic table. It is necessary to know the atomic number of lithium elements from the periodic table.

position of lithium in the periodic table
The position of lithium in the periodic table

The atomic number is the number of protons. And electrons equal to protons are located outside the nucleus. That is, we can finally say that there are electrons equal to the atomic number in the lithium atom. From the periodic table, we see that the atomic number of lithium is three. That is, a lithium atom has a total of three electrons.

Step-2: Need to do electron configuration

Step 2 is very important. In this step, the electrons of lithium have to be arranged. We know that lithium atoms have a total of three electrons. The electron configuration of lithium shows that there are two electrons in the K shell and one in the L shell.

That is, the first shell of lithium has two and the second shell has one electron. The electron configuration of lithium through the sub-orbit is 1s2 2s1.

Lithium Electron Configuration
Lithium Electron Configuration

Step-3: Determining the valence shell(orbit) and calculate total electrons

The third step is to diagnose the valence shell. The last shell after the electron configuration is called the valence shell. The total number of electrons in a valence shell is called a valence electron.

The electron configuration of lithium shows that the last shell of lithium has only one electron. Therefore, the valence electron of lithium is one. In this way, the valence electrons of all the elements can be determined.

Determination of the valency of lithium

The ability to bind one atom to another and form compounds is called valency(valence). There are some rules for diagnosing valency. The number of electrons in an unpaired state in the last orbital after the electron configuration of an atom is called the valency of that element.

The electron configuration of lithium is 1s2 2s1. The electron configuration of lithium shows that lithium has one electron in the last orbital. Therefore, the valency(valence) of lithium is 1.

valence electrons of lithium
Valence Electrons of Lithium

How many valence electrons of lithium ion have?

After the electron configuration, the last shell of the lithium atom has an electron. In this case, both the valence and valence electrons of lithium are 1. We know the details about this. The elements that have 1, 2, or three electrons in the last shell donate the electrons in the last shell during bond formation.

The elements that form bonds by donating electrons are called cations. That is, lithium is a cation element. Lithium donates the electrons of the last shell to form bonds and turns into lithium ions.

Li – e → Li +

The electron configuration of lithium ions is 1s2. The electron configuration of lithium ions shows that lithium ions have only one shell and that shell has 2 electrons. The electron configuration shows that the lithium atom has acquired the electron configuration of helium.

That is, in this case, the valence of the lithium-ion is +1. Since the last shell of a lithium-ion has 2 electrons, the valence electrons of a lithium-ion are two.

Compound formation of lithium by valence electrons

Lithium participates in the formation of bonds through its valence electrons. We know that the valence electron in lithium is one. This valence electron participates in the formation of bonds with atoms of other elements. The electron configuration of fluorine shows that the valence electrons of fluorine are seven.

LiF bonding
LiF bonding

The lithium atom donates its valence electron to the fluorine atom and the fluorine atom receives that electron. As a result, fluorine acquires the electron configuration of neon and the lithium atom acquires the electron configuration of helium. Fluorine and lithium atoms form lithium fluoride(LiF) bonds through electron exchange. Lithium fluoride(LiF) bond is ionic bonding.

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