Question

What is the electronic configuration for tin?
 $\begin{align}
  & \text{A}\text{. }\!\![\!\!\text{ Kr }\!\!]\!\!\text{ 5}{{\text{s}}^{\text{2}}}\text{5}{{\text{p}}^{\text{2}}} \\
 & \text{B}\text{. }\!\![\!\!\text{ Kr }\!\!]\!\!\text{ 4}{{\text{d}}^{\text{10}}}\text{5}{{\text{s}}^{\text{2}}}\text{5}{{\text{p}}^{\text{2}}} \\
 & \text{C}\text{.1}{{\text{s}}^{\text{2}}}\text{2}{{\text{s}}^{\text{2}}}\text{2}{{\text{p}}^{\text{6}}}\text{3}{{\text{s}}^{\text{2}}}\text{3}{{\text{p}}^{\text{6}}}\text{3}{{\text{d}}^{\text{10}}}\text{4}{{\text{s}}^{\text{2}}}\text{4}{{\text{p}}^{\text{2}}} \\
 & \text{D}\text{. }\!\![\!\!\text{ Kr }\!\!]\!\!\text{ 4}{{\text{d}}^{\text{11}}}\text{5}{{\text{s}}^{\text{2}}}\text{5}{{\text{p}}^{\text{1}}} \\
\end{align}$

Answer 1

Hint:To answer this question the information of tin atomic number must be known. The tin has an atomic number of 50, which means tin has 50 electrons. Thus, Aufbau principle will be utilized to solve the question.

Complete step by step answer:
The electronic configuration can be described via Aufbau principle.
This principle states that the electrons of an atom or ions, that are in ground state, fill the orbital of lower energy first then they enter to the highest energy orbital.
For example, the electrons first enter to 1s then 2s then 2p, 3s, 3p, 4s, 3d and so on.
The atom or ions are most stable when the s, p, d, f orbital are fully or half filled with electrons.
Tin (symbol – Sn) has an atomic number 50. It means it has 50 electrons.
Here, as the electron of tin reaches and fulfil the vacant orbitals it would be filling the orbital as following according to the Aufbau principle i.e. 1s, 2s,2p,3s,3p,4s,3d,4p,5s,4d and 5p orbitals.
Tin lies in the group-14 of the periodic table, so it’s electronic configuration will be similar to the carbon.
So the electronic configuration is $\text{1}{{\text{s}}^{\text{2}}}\text{2}{{\text{s}}^{\text{2}}}\text{2}{{\text{p}}^{\text{6}}}\text{3}{{\text{s}}^{\text{2}}}\text{3}{{\text{p}}^{\text{6}}}\text{3}{{\text{d}}^{\text{10}}}\text{4}{{\text{s}}^{\text{2}}}\text{4}{{\text{p}}^{\text{6}}}\text{4}{{\text{d}}^{\text{10}}}\text{5}{{\text{s}}^{\text{2}}}\text{5}{{\text{p}}^{\text{2}}}$ or \[\text{ }\!\![\!\!\text{ Kr }\!\!]\!\!\text{ 4}{{\text{d}}^{\text{10}}}\text{5}{{\text{s}}^{\text{2}}}\text{5}{{\text{p}}^{\text{2}}}\]as Krypton has electronic configuration $\text{1}{{\text{s}}^{\text{2}}}\text{2}{{\text{s}}^{\text{2}}}\text{2}{{\text{p}}^{\text{6}}}\text{3}{{\text{s}}^{\text{2}}}\text{3}{{\text{p}}^{\text{6}}}\text{3}{{\text{d}}^{\text{10}}}\text{4}{{\text{s}}^{\text{2}}}\text{4}{{\text{p}}^{\text{6}}}$.
So, the correct answer is option-B.

Note:
Aufbau principle describes the manner of electrons filled in an atomic orbital of an atom in the ground state configuration. The principle stated that, based on the energy level of atomic orbital electron fills happen. The electron fills to the respective atomic orbital happens with the fact that lowest energy orbitals are first occupied by electrons, if they completely fill then in the higher energy level orbitals start to be occupied by electrons.