MN2+ Electron Configuration: 3 Facts to Consider


The lowest oxidation state of manganese (Mn) metal is +2. Several physical and chemical properties like the magnetism, magnetic moment, color, ionic state etc. of Mn2+ can be determined by its Mn2+ electron configuration.

Mn2+ electron configuration is 1s2 2s2 2p6 3s2 3p6 3d5 and its condensed and noble gas electronic configuration is [Ar]3d54s0

Mn2+ ion electron configuration

The electronic configuration of Mn2+ ion is 1s2 2s2 2p6 3s2 3p6 3d5. It can also be written as 1s2 2s2 2px2 2py2 2pz2 3s2 3px2 3py2 3pz2 3dxy1 3dyz1 3dxz1 3dx2-y21 3dz21.

Mn2+ ion is a cation transition metal belonging to d block elements in the periodic table, having 2 electrons less than that of the manganese metal atom.

How to find the electronic configuration of Mn2+ ion?

To arrive at the electronic configuration of Manganese (Mn2+) ion, electrons are to be added in the order in different sublevels according to Aufbau principle, Pauli’s exclusion principle and Hund’s rule.

1)First determine the number of electrons present in manganese (Mn2+) ion.

The number of electrons present in Mn2+ ion is 23. It is the total number of electrons present after the removal of 2 electrons from Manganese (Mn) metal which has total 25 electrons.

2)Electrons enter the available sublevel shells in the increasing order of their energy levels.

The increasing energy level order is as, 1s 2s 2p 3s 3p 3d (Mn2+ ion).

3)The sub shells should be filled or half filled before the electrons enter the next sub shell level.

S subshell can hold maximum two electrons, p subshell can hold six electrons and d subshell can hold ten electrons.

                                1s2 2s2 2p6 3s2 3p6 3d5

                              2+2+6+2+6+5=23

This is how the electronic configuration of Mn2+ ion is determined.

The mn2+ electron configuration box diagram of manganese (Mn2+) can be represented as,

mn2+ electron configuration

mn2+ electron configuration box diagram

From the representation of the electronic configuration box diagram of Mn2+ ion we can see that the five electrons in the 3d orbitals are not paired making its magnetism paramagnetic in nature.

Mn2+ ground-state electron configuration

The ground state electronic configuration of Mn2+ ion is 1s2 2s2 2p6 3s2 3p6 3d5.

Mn2+ ion is formed by the loss of two electrons from manganese (Mn) metal by ionization.

mn2+ electron configuration

mn2+ electron configuration loss of 2 electrons by Mn

DeltaiH is the ionization enthalpy required to remove two electrons from manganese (Mn) metal, and its value is 1509 KJ/Mol.

As the atomic number of the manganese (Mn) atom is 25 ie, there are 25 electrons present in the manganese atom, and so its electronic configuration can be written as,

                                                   1s2 2s2 2p6 3s2 3p6 3d54s2

When two electrons are lost from the manganese metal atom by ionisation then the number of electrons in Mn2+ ion becomes 23. Then the mn2+ electron configuration can be written as,

                                                   1s2 2s2 2p6 3s2 3p6 3d5

The two electrons of the manganese atom are lost from the 4s orbitals and not from 3d orbitals.

 The reason for it is that when electrons are filled in the orbitals according to their increasing energy level, the 4s orbitals have lower energy than that of the 3d orbitals. Due to this reason that after filling up to the 3p orbitals, the electrons are first filled up in the 4s orbitals, and then the 3d orbitals are filled.

But when the electrons are removed from the sub shells then it is first removed from 4s orbital and not from 3d orbitals, even though 4s orbitals have lower energy than that of the 3d orbitals.

When considering its distance from the nucleus, the 4s orbitals are much farther away from the nucleus than the 3d orbitals, and so the electrons of the 4s orbitals experience less nuclear attraction compared to the electrons of the 3d orbitals, making it easier for the electrons to be removed from the 4s orbitals than the 3d orbitals.

Mn2+ condensed electron configuration

The condensed electronic configuration of Mn2+ ion is represented as [Ar] 3d5 or it can also be represented as [Ar] 3d54s0.

The electronic configuration of atoms gets longer gradually with the increase in its atomic number as the number of electrons in an atom increases with atomic number and because of that representing of the electronic configuration of the atoms with higher atomic number gets complicated.

 In order to overcome these complications condensed electronic configuration has come to play its role.

The mn2+ electron configuration of ; 1s2 2s2 2p6 3s2 3p6 3d5

The electronic configuration of Ar (Argon) is; 1s2 2s2 2p6 3s2 3p6

So, in Mn2+ electron configuration up to 3p6 configuration is the electronic configuration of argon (Ar) noble gas atom and hence we can represent the configuration up to 3p6 as Ar, symbol of argon placed in a bracket and the remaining electronic configuration after that is written as it is making it simple and easy to understand.

Mn2+ noble gas electron configuration

The noble gas electronic configuration of Mn2+ ion is [Ar]3d5. Noble gas electronic configuration of Mn2+ ion can be represented by noting the nearest noble gas prior to Mn i.e. the argon (Ar) gas its symbol Ar in a bracket followed by writing down the electronic configuration coming after that.

Noble gas electronic configuration is a common short hand notation to represent the electronic configuration of atoms to make it short rather than to write out the entire electronic configuration

The reason for representing the configuration with a noble gas is because the electrons are filled in up to its full capacity and can no longer accommodate any electrons and because of that they are highly stable and considered least reactive making it easier to use its configuration as inner shell of other atoms and represent.

This is also the cause why most of the atoms having atomic number near to noble gas always try to achieve noble gas electronic configuration by either gaining or losing electrons. Argon has an atomic number 18 and fully filled electronic configuration and because of that they are highly stable atom present near manganese.

The compounds of manganese in+2 oxidation is known as manganous compounds. Manganese in +2 oxidation state is considered more stable than its other oxidation state, it can be explained by its extra stability of half-filled 3d orbitals.

Mn2+ is ionic in nature because it will be easier for the metal to lose fewer electrons in its ionic character and also show basic nature. They exhibit pale pink color.

Conclusion –

Through this article we have studied and learnt that the electronic configuration of Mn2+ ion is 1s2 2s2 2p6 3s2 3p6 3d5 and its condensed and noble gas electronic configuration is [Ar]3d5.

Recent Posts