Question

What is the electronic configuration for manganese?
A.\[1{s^2}2{s^2}2{p^6}3{s^2}3{p^5}\]
B.\[\left[ {Ar} \right]4{s^1}\]
C.\[1{s^2}2{s^2}2{p^6}3{s^2}3{p^5}4{s^2}3{d^5}\]
D.\[1{s^2}2{s^2}3{p^1}\]

Answer 1

Hint: First we have to know that manganese having the element symbol \[Mn\]is a transition metal with atomic number of 25. So we can write the electronic configuration with the help of Aufbau Principle.

Complete step by step answer:
Let’s start with discussing a little about electronic configuration to get a better understanding about the question. Electronic configurations tell us about how the electrons are distributed in the atom between different atomic orbitals. Electrons are always placed in a sequence and the sequence is described using the Aufbau Principle.
Now coming back to the question, we are provided with the element Manganese. Manganese is an element with the symbol \[Mn\] and the atomic number of 25. When we take aufbau principle into consideration, the first 1s orbital is filled followed by 2s, 2p, 3s, 3p, 4s, 3d, 4p and so on. s orbital contains 2 electron max, p orbitals contains 6 electron max and d orbitals contain 10 electron max.
So an element with 25 electrons will have electronic configuration as
\[1{s^2}2{s^2}2{p^6}3{s^2}3{p^6}4{s^2}3{d^5}\], this configuration also shows that the element is a transition metal present in d-block of periodic table.

So, the answer to this question is option \[C.{\text{ }}1{s^2}2{s^2}2{p^6}3{s^2}3{p^6}4{s^2}3{d^5}\].

Note:
We must know that the electronic configurations tell not only about the orbitals electrons are present but also about the stability of these atoms. A fully filled orbital is always more stable than the half-filled orbital and the half-filled orbitals are more stable than the other orbital configurations. Hence, it is seen that some elements just to achieve half-filled or fully filled orbitals take electrons from other orbitals just to achieve a more stable configuration.