How many valence electrons does sodium(Na) have?
Sodium(Na) is the eleventh element in the periodic table. Sodium is an alkali metal and its symbol is ‘Na’. Sodium atoms participate in the formation of bonds through valence electrons. This article discusses in detail the valence electrons of sodium. Hopefully, after reading this article you will know in detail about this.
Table of Contents
How many electrons, protons and neutrons does a sodium(Na) atom have?
The nucleus is located in the center of the atom. Protons and neutrons are located in the nucleus. The atomic number of sodium(Na) is 11. The atomic number is the number of protons. That is, the number of protons in the sodium is eleven. Electrons equal to protons are located in a circular shell(orbit) outside the nucleus. That is, the sodium atom has a total of eleven electrons.
The number of neutrons in an element is obtained from the difference between the number of atomic masses and the number of atoms. That is, neutron number (n) = atomic mass number (A) – atomic number (Z)
We know that the atomic number of sodium is 11 and the atomic mass number is about 23(22.989769). Neutron (n) = 23 – 11 = 12. Therefore, the number of neutrons in sodium(Na) is 12.
What are the valence electrons of sodium(Na)?
Sodium is an element of group-1. The valence electron is the total number of electrons in the last orbit(shell). The total number of electrons in the last shell after the electron configuration of sodium is called the valence electrons of sodium(Na). The valence electrons determine the properties of the element and participate in the formation of bonds.

The electron configuration of sodium(Na) shows that the last shell(orbit) of sodium has a total of an electron. There is an article on this site detailing the electron configuration of sodium(Na), you can read it if you want.
How do you calculate the number of valence electrons in a sodium(Na) atom?
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.
However, valence electrons can be easily identified by arranging electrons according to the Bohr principle. Now we will learn how to determine the valence electrons of sodium(Na).
Step-1: Determining the total number of electrons in sodium(Na)
First we need to know the total number of electrons in the sodium(Na) atom. To know the number of electrons, you need to know the number of protons in sodium. And to know the number of protons, you need to know the atomic number of the sodium 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 sodium(Na) elements from the periodic table. The atomic number is the number of protons and electrons equal to protons located outside the nucleus.
That is, we can finally say that there are electrons equal to the atomic number in the sodium(Na) atom. From the periodic table, we see that the atomic number of sodium(Na) is 11. That is, a sodium(Na) atom has a total of eleven electrons.
Step-2: Need to do electron configuration of sodium(Na)
Step 2 is very important. In this step, the electrons of sodium(Na) have to be arranged. We know that sodium atoms have a total of eleven electrons. The electron configuration of sodium(Na) shows that there are two electrons in the K shell, eight in the L shell, and one in the M shell(orbit).

That is, the first shell of sodium has two electrons, the second shell has eight electrons and the 3rd shell(orbit) has one electron. The electron configuration of sodium(Na) through the sub-orbit is 1s2 2s2 2p6 3s1.
Step-3: Determine the valence shell and calculate total electrons
The third step is to diagnose the valence shell(orbit). 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 sodium shows that the last shell of sodium has an electron(3s1). Therefore, the valence electrons of sodium(Na) are one.
What is the valency of sodium(Na)?
The ability of one atom of an element to join another atom during the formation of a molecule is called valency(valence). The number of unpaired electrons in the last orbit of an element is the valency of that element.

The electron configuration of sodium(Na) shows that there is an unpaired electron in the last orbit of sodium. Therefore, the valency of sodium is 1.
How many valence electrons does sodium ion(Na+) have?
After the electron configuration, the last shell of the sodium atom has an electron. In this case, the valency of sodium is 1. We know the details about this. The elements that have 1, 2, or 3 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, sodium is a cation element. Sodium donates the electron of the last shell to form bonds and turns into sodium ions.
Na – e– → Na+
The electron configuration of sodium ion(Na+) is 1s2 2s2 2p6. The electron configuration of sodium-ion shows that sodium ions have only two shells and the last shell has eight electrons.
The electron configuration shows that the sodium atom has acquired the electron configuration of neon. That is, in this case, the valency of the sodium-ion is +1. Since the last shell of a sodium-ion has eight electrons, the valence electrons of sodium ion(Na+) are eight.
Compound formation of Sodium(Na)
Sodium participates in the formation of bonds through its valence electron. We know that the valence electron in sodium is one. This valence electron participates in the formation of bonds with atoms of other elements.
The electron configuration of chlorine shows that the valence electrons of chlorine are seven. The sodium atom donates its valence electron to the chlorine atom and the chlorine atom receives that electron.

As a result, chlorine acquires the electron configuration of argon and, the sodium atom acquires the electron configuration of neon. Chlorine and sodium atoms form sodium chloride(NaCl) bonds through electron exchange. Sodium chloride(NaCl) is ionic bonding.