Question

Transition metals have the general electronic configuration:
A.${\text{n}}{{\text{s}}^2}{\text{n}}{{\text{d}}^{1 - 10}}$
B.${\text{n}}{{\text{s}}^2}{\text{n}}{{\text{p}}^1}\left( {{\text{n}} - 1} \right){{\text{d}}^{1 - 10}}$
C.\[{\text{n}}{{\text{s}}^{{\text{1 - 2}}}}\left( {{\text{n}} - {\text{1}}} \right){{\text{d}}^{{\text{1 - 10}}}}\]
D.\[{\text{n}}{{\text{s}}^{\text{2}}}{\text{n}}{{\text{p}}^{\text{6}}}\left( {{\text{n}} - {\text{1}}} \right){{\text{d}}^{{\text{1 - 10}}}}\]

Answer 1

Hint: To answer this question, you should recall the formation of the periodic table. The transition elements are also known as d-block elements. The last electron is filled in the d-orbital of the penultimate shell.

Complete step by step answer:
There are 4 blocks in the periodic table: s-block, p-block, d-block and f-block. All of the s-block elements are metals.
The p-block due to its ability to accommodate a large number of electrons has the biggest variety of elements and is the only block that contains three types of elements: metals, nonmetals and metalloids.
The d-block elements have properties that are between s-block elements and p-block elements properties. It consists of transition metals. The f-block elements are mostly radioactive.
Electronic configuration of transition metal is:
\[ \Rightarrow \;\left[ {{\text{Noble gas}}} \right]\;n{s^{1 - 2}}\left( {n - 1} \right){d^{1 - 10}}\]
For example- Chromium has \[\left[ {Ar} \right]4{s^1}3{d^5}\]

Hence, the correct answer is option C.

Note:
The electronic configuration of elements is based on majorly 3 rules:
According to Pauli's exclusion principle in an atom, no two electrons will have an identical set or the same quantum numbers. There salient rules of Pauli Exclusion Principle are that only two electrons can occupy the same orbital and the two electrons that are present in the same orbital should be having opposite spins.
According to Hund’s Rule of Maximum Multiplicity rule for a given electronic configuration of an atom, the electron with maximum multiplicity falls lowest in energy.
According to the Aufbau principle, the electrons will start occupying the orbitals with lower energies before occupying higher energy orbitals.