Question

Consider the following statement and choose the correct option:
The outermost configuration of the least reactive element is:
A) $n{s^2}n{p^3}$
B) $n{s^2}n{p^4}$
C) $n{s^2}n{p^5}$
D) $n{s^2}n{p^6}$

Answer 1

Least reactive elements have a completely filled outermost configuration. They do not show any tendency to further gain or lose electrons. For example, noble gases are the least reactive elements, which are also called inert gas.

Complete step by step answer:
Least reactive elements lack participation in any chemical reactions. They are least reactive because their outermost electron shells or valence shells are completely filled. They are the most stable for having the completely filled outermost configuration, that is, $n{s^2}n{p^6}$. So, they do not show any tendency to further gain or lose electrons. Least reactive elements require a lot of energy to form a bond as they have the completely filled valence shell.
Hence the correct option is D.

Additional information: Least reactive elements are placed in group 18 of the periodic table, the noble gases (Helium, Neon, Argon, Krypton, Xenon, and Radon). They lack participation in any chemical reactions for which they are called inert gas, having the inert gas configuration. Irrespective of not participating in any reactions, inert gases have a range of uses. For example, these gases are used to form the inert atmosphere, such as for the arc welding, to protect specimens, and to prevent chemical reactions, etc.

Note:
In today’s research it is now shown that the least reactive metals also do react with other chemical compounds. But, to drive the reactions, a higher amount of heat, radiation, catalysts, and pressure are needed. Also, there are so many measures to be taken to keep the newly made compound intact to prevent rapid decomposition.