What Is Astatine?

Astatine, the eighty-fifth element on the periodic table, is a rare, radioactive halogen. It's so scarce, it's barely a whisper in nature.

Atomic Number: 85

Symbol: At

Atomic Mass: [210] u (most stable isotope)

Category: Halogen

State at Room Temperature: Solid (presumed)

Discovered By: Dale R. Corson, Kenneth Ross MacKenzie, Emilio Segrè (1940)

⚛️ Atomic Structure of Astatine

Astatine has eighty-five protons, one hundred twenty-five neutrons (in its most stable isotope, Astatine-210), and eighty-five electrons, with seven in its outer shell.

  • 🟢 Protons: 85
  • 🔴 Neutrons: 125 (Most stable isotope, Astatine-210)
  • 🟡 Electrons: 85

💡 Did you know? All Astatine on Earth weighs less than a sugar cube!

🔬 Astatine Properties

Astatine is radioactive, likely metallic, and dark. It melts around 302°C (576°F, estimated), but its short half-life makes it hard to study.

🧪 How Was Astatine Discovered?

In 1940, Dale R. Corson, Kenneth Ross MacKenzie, and Emilio Segrè synthesized Astatine at UC Berkeley, naming it from Greek "astatos" (unstable).

⚡ Uses of Astatine

  • 🩺 Medicine: Experimental cancer therapy.
  • 🔬 Research: Studying halogens.
  • ☢️ Limited: Too rare for much else.

💡 Fun Facts About Astatine

  • 🌍 Rarest natural element.
  • ⏳ Half-life of 8 hours.
  • 🔥 Vanishes fast.
  • 🧪 Synthetic origin.

⚠️ Safety & Precautions

Astatine is highly radioactive and toxic. Avoid all contact; handle only in specialized labs with radiation safeguards.

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