Which of the following best explains why noble gases do not react much with other elements?

• A. Their atoms are too large to form chemical bonds with other elements.
• B. Their outer electron shells are completely filled, making them chemically stable.
• C. They have very low atomic masses, preventing chemical reactions.
• D. They have the highest metallic character among all elements.

Answer: (B)

Verified step by step guidance

1. Understand that chemical reactivity is largely determined by the electron configuration of an element, especially the electrons in the outermost shell (valence electrons).
2. Recall that noble gases have completely filled outer electron shells, meaning their valence shells have the maximum number of electrons allowed by the shell's capacity.
3. Recognize that a full valence shell corresponds to a very stable electronic configuration, which means noble gases have little tendency to gain, lose, or share electrons to form chemical bonds.
4. Evaluate the other options: atomic size, atomic mass, and metallic character do not primarily determine the chemical inertness of noble gases.
5. Conclude that the best explanation for the low reactivity of noble gases is their completely filled outer electron shells, which make them chemically stable and unlikely to react.