The 25th element in the periodic table is manganese. The element of group-7 is manganese and its symbol is ‘Mn’. Manganese is a transition element. Therefore, the valence electrons of manganese are determined differently.
The last shell(orbit) of a manganese element has only two electrons but its valence electrons are not two. This article discusses in detail the valence electrons of manganese. Hopefully, after reading this article you will know in detail about the valence electrons of manganese(Mn).
Table of Contents
How many electrons and protons does manganese(Mn) have?
The nucleus is located in the center of the atom. Protons and neutrons are located in the nucleus. The atomic number of manganese(Mn) is 25. The atomic number is the number of protons.
That is, the number of protons in manganese is twenty-five. Electrons equal to protons are located in a circular shell outside the nucleus. That is, a manganese atom has a total of twenty-five electrons.
What are the valence electrons of manganese(Mn)?
The 1st element in group-7 is manganese and this is the d-block element. The elements in groups 3-12 are called transition elements. The valence electron is the total number of electrons in the last orbit(shell).
But in the case of transition elements, the valence electrons remain in the inner shell(orbit). This is because the electron configuration of the transition elements shows that the last electrons enter the d-orbital.
The electron configuration of manganese shows that the last shell(orbit) of manganese has a total of two electrons. But the electron configuration of manganese in the Aufbau method shows that its last electron(3d5) has entered the d-orbital.
The valence electrons determine the properties of the element and participate in the formation of bonds. The electrons of the d-orbital participate in the formation of bonds. So, To determine the valence electron of a transition element, the last shell(orbit) electrons have to be calculated with the d-orbital electrons.
That is, we can easily say that manganese(Mn) has seven valence electrons. There is an article on this site detailing the electron configuration of manganese, you can read it if you want.
How to determine the manganese(Mn) valence electron?
Now we will know how to easily determine the valence electron of manganese. 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. The valence electrons of the transition element cannot be determined according to Bohr’s atomic model. This is because the valence electrons of the transition elements are located in the inner shell(orbit).
The German physicist Aufbau first proposed an idea of electron configuration through sub-orbits. The Aufbau method is to do electron configuration through the sub-energy level.
These sub-orbitals are expressed by ‘l’. The Aufbau principle is that the electrons present in the atom will first complete the lowest energy orbital and then gradually continue to complete the higher energy orbital. These orbitals are named s, p, d, f. The electron holding capacity of these orbitals is s = 2, p = 6, d = 10 and f = 14.
However, the valence electron of the transition element can be easily determined according to the Aufbau principle. Now we will learn how to determine the valence electron of manganese(Mn).
Step-1: Determining the total number of electrons
1st we need to know the total number of electrons in the manganese(Mn) atom. To know the number of electrons, you need to know the number of protons in manganese. And to know the number of protons, you need to know the atomic number of the manganese 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 manganese elements from 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 manganese(Mn) atom. From the periodic table, we see that the atomic number of manganese is 25. That is, the manganese atom has a total of twenty-five electrons.
Step-2: Need to do electron configuration
Step 2 is very important. In this step, the electrons of manganese have to be arranged. We know that manganese atoms have a total of twenty-five electrons. The electron configuration of manganese shows that there are two electrons in the K shell, eight in the L shell, thirteen in the M shell, and two in the N shell(orbit).
That is, the first shell of manganese(Mn) has two electrons, the second shell has eight electrons, the 3rd shell has thirteen electrons and the 4th shell(last orbit) has two electrons. The number of electrons per shell of manganese is 2, 8, 13, 2. The electron configuration of manganese through the sub-orbit is 1s2 2s2 2p6 3s2 3p6 4s2 3d5.
Step-3: Determining the valence shell(orbit) 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(orbit). The total number of electrons in a valence shell is called a valence electron.
But the valence electrons of the transition elements are located in the inner orbit(shell). For the transition element, the valence electron has to be determined by adding the total electron of the d-orbital to the electron in the last orbit of the atom.
The electron configuration of manganese shows that the last shell of manganese has two(4s2) electrons and the d-orbital has a total of five electrons(3d5). Therefore, the valence electrons of manganese(Mn) are seven. In this way, the valence electrons of all the transition elements can be determined.
How to determine the valency of manganese?
The ability of one atom of an element to join another atom during the formation of a molecule 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 oxidation states of manganese(Mn) depend on the bond formation. The oxidation states of manganese are +2, +3, +4, +6, +7.
The oxidation state of manganese +2 has been used in the manganese(II) oxide(MnO) bond. The valency of manganese in this compound is 2.
On the other hand, The oxidation state of manganese +7 has been used in permanganate ion (MnO4)1-. The valency of manganese in this compound is 7.
How many valence electrons does manganese ion(Mn2+, Mn3+ Mn4+) have?
The electron configuration of manganese shows that the last shell of manganese has two(4s2) electrons and the d-orbital has a total of five electrons. There are three types of manganese ions. The ionic state of the element changes depending on the bond formation. Mn2+, Mn3+ and Mn4+ ions are more abundant in the manganese atom.
Mn – 2e– → Mn2+
Here, The electron configuration of manganese ion(Mn2+) is 1s2 2s2 2p6 3s2 3p6 3d5. The electron configuration of manganese ion shows that manganese ion has three shells and that shell has thirteen electrons (3s2 3p6 3d5). For this, manganese ion(Mn2+) has a total of thirteen valence electrons.
Mn – 3e– → Mn3+
On the other hand, The electron configuration of manganese ion(Mn3+) is 1s2 2s2 2p6 3s2 3p6 3d4. The electron configuration of manganese ion shows that manganese ion has three shells and that shell has twelve electrons (3s2 3p6 3d4). Here, the valence electrons of the manganese ion(Mn3+) are twelve.
Again, Mn – 4e– → Mn4+
The electron configuration of manganese ion(Mn4+) is 1s2 2s2 2p6 3s2 3p6 3d3. The electron configuration of manganese ion shows that manganese ion has three shells and that shell has eleven electrons(3s2 3p6 3d3). Here, the valence electrons of manganese ion(Mn4+) are eleven.
Compound formation of manganese
Manganese(Mn) participates in the formation of bonds through its valence electrons. We know that the valence electrons in manganese are seven. This valence electron participates in the formation of bonds with atoms of other elements.
The electron configuration of oxygen shows that the valence electrons of oxygen are six. The manganese atom donates its valence electrons to the oxygen atom and the oxygen atom receives those electrons.
As a result, oxygen acquires the electron configuration of neon. Manganese(III) oxide (Mn2O3) is formed by the exchange of electrons between two atoms of manganese and three atoms of oxygen. Manganese(III) oxide (Mn2O3) is ionic bonding.
