Noble Gas Radioactivity Explained

Noble gases (Group 18 elements) are known for their stability due to a full valence electron shell, making them generally unreactive. However, one noble gas stands out due to its radioactivity.

Identifying the Radioactive Noble Gas

Let's examine the options:

• Neon (Ne): A stable, non-radioactive noble gas.
• Krypton (Kr): Primarily exists as stable isotopes. While some isotopes are radioactive, it's not inherently radioactive like Radon.
• Argon (Ar): A stable, non-radioactive noble gas commonly found in the atmosphere.
• Radon (Rn): This noble gas is inherently unstable and radioactive. It originates from the decay of radioactive elements like uranium and radium. All its isotopes decay relatively quickly.

Conclusion on Radioactivity

Therefore, Radon is the radioactive noble gas among the choices.