Question

Which Noble gas does not have Octet complete?
A helium
B neon
C krypton
D argon

Answer 1

The octet rule is a chemical rule of thumb that represents the hypothesis that main-group elements tend to bind in such a way that each atom has eight electrons in its valence shell, resulting in an electronic configuration similar to that of a noble gas. The law applies to carbon, nitrogen, oxygen, and halogens in particular, but also to metals like sodium and magnesium.

Complete answer:
The noble gases are a group of chemical elements with comparable characteristics; they are all odourless, colourless, monatomic gases with very little chemical reactivity under normal conditions. The characteristics of noble gases are well explained by current atomic structure theories: Only a few hundred noble gas compounds have been prepared because their outer shell of valence electrons is deemed "full," giving them little propensity to participate in chemical processes.
The valence electron shells of noble gases are full. Valence electrons are an atom's outermost electrons and are usually the sole ones involved in chemical bonding. Atoms with complete valence electron shells are highly stable, and as a result, they seldom form chemical bonds or receive or lose electrons. However, electromagnetic force holds heavier noble gases like radon less securely together than lighter noble gases like helium, making it easier to remove outer electrons from heavy noble gases.
The electrical configuration of helium is $1{{s}^{2}}$. As a result, the arrangement does not feature an octet. It's a stale, flavourless, odourless, non-harmful monoatomic gas. It has a boiling point, which is the least of the many other components. All other noble gases have a configuration of $n{{s}^{2}}n{{p}^{6}}$

Hence option a is correct.

Note:
Some noble gases have direct medical use. Asthma sufferers may benefit from the usage of helium to make breathing easier. Xenon is utilised as an anaesthetic because of its high solubility in lipids, making it more powerful than nitrous oxide, and because it is easily excreted from the body, allowing for quicker recovery. Through hyperpolarized MRI, xenon is used in medical imaging of the lungs. In radiation, radon is utilised, which is extremely radioactive and only available in trace amounts.