The stability of the noble gases is due to the fact that they?

Analysis

The question asks for the fundamental reason behind the chemical inertness (stability) of noble gases (Group 18 elements).

Concept Explanation

In chemistry, atoms tend to react and form bonds to achieve a stable electronic configuration. This is often referred to as the Octet Rule.

• Octet configuration: Most atoms aim to have 8 electrons in their outermost shell (valence shell) to become stable, similar to the noble gas Neon, Argon, etc.
• Duplet configuration: Helium, being the first noble gas, is stable with only 2 electrons in its outermost shell (the 1s orbital).

Noble gases are already "satisfied" because their outermost shells are completely filled. They do not need to gain, lose, or share electrons with other atoms, which is why they are chemically inert (unreactive).

Step-by-Step Solution

1. Evaluate Option A: This is incorrect. Noble gases have electrons in their outermost shells; they are just fully occupied.
2. Evaluate Option B: This is correct. Helium has a stable duplet (2 electrons), while Neon, Argon, Krypton, Xenon, and Radon have a stable octet (8 electrons). This full configuration prevents them from reacting under normal conditions.
3. Evaluate Option C: While it is true that they belong to Group 0 (or Group 18), this is a classification, not the reason for their stability. The stability is the cause of their position in the table, not the other way around.
4. Evaluate Option D: Volatility refers to how easily a substance turns into a gas. While noble gases are gases, their volatility is a physical property, not the reason for their chemical stability.

Conclusion

The chemical stability of noble gases is directly attributed to their electronic structure, which consists of either a duplet (for Helium) or an octet (for the others) of electrons in their valence shells.

Exam Tip: Whenever you see a question about the reactivity of elements, always look for the option that mentions "valence electrons" or "octet/duplet configuration." These are the keys to understanding chemical bonding!