Write the complete ground-state electron configuration of Mn^4+.
The Correct Answer and Explanation is:
Correct Answer:
The ground-state electron configuration of Mn⁴⁺ is:
[Ar] 3d³
Explanation
To determine the ground-state electron configuration of Mn⁴⁺, we begin with the neutral manganese (Mn) atom. Manganese has an atomic number of 25, meaning it contains 25 electrons in its neutral state. The electron configuration for neutral Mn is:
Mn: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁵,
or using noble gas notation:
[Ar] 4s² 3d⁵
When manganese loses electrons to form a positive ion (Mn⁴⁺), it loses a total of 4 electrons. The removal of electrons follows a specific order. Electrons are removed from the outermost shell first. This means that the 4s electrons are removed before the 3d electrons.
So, the electron removal process for Mn⁴⁺ proceeds as follows:
- Remove 2 electrons from 4s² → becomes 4s⁰
- Remove 2 electrons from 3d⁵ → becomes 3d³
This results in the configuration:
[Ar] 3d³
This is the ground-state configuration of the Mn⁴⁺ ion.
The reason the 4s electrons are removed before the 3d electrons is due to energy levels. Although the 4s orbital is filled before the 3d orbital in a neutral atom, once filled, the 4s electrons are higher in energy and are therefore more easily removed during ionization. This pattern is common among transition metals.
Manganese in the +4 oxidation state is relatively uncommon but can be found in certain compounds, such as manganese dioxide (MnO₂), where Mn has a +4 charge. In these cases, Mn⁴⁺ plays an important role in redox reactions and catalytic cycles, particularly in environmental and biological systems.
Understanding electron configurations of ions helps predict chemical behavior, bonding, and reactivity.
