What Is Actinium?

Actinium, the eighty-ninth element on the periodic table, is a rare, radioactive actinide that glows faintly and kickstarts the actinide series.

Atomic Number: 89

Symbol: Ac

Atomic Mass: [227] u (most stable isotope)

Category: Actinide

State at Room Temperature: Solid

Discovered By: André-Louis Debierne (1899)

⚛️ Atomic Structure of Actinium

Actinium has eighty-nine protons, one hundred thirty-eight neutrons (in its most stable isotope, Actinium-227), and eighty-nine electrons, with two in its outer shell.

  • 🟢 Protons: 89
  • 🔴 Neutrons: 138 (Most stable isotope, Actinium-227)
  • 🟡 Electrons: 89

💡 Did you know? Actinium glows pale blue in the dark due to its radioactivity!

🔬 Actinium Properties

Actinium is radioactive, silvery, and soft. It emits alpha and beta particles and has a melting point of about 1050°C (1922°F).

🧪 How Was Actinium Discovered?

In 1899, French chemist André-Louis Debierne discovered Actinium while working with pitchblende, identifying it as a new radioactive element.

⚡ Uses of Actinium

  • 🩺 Medicine: Targeted alpha therapy for cancer.
  • 🔬 Research: Studying radioactivity.
  • ⚡ Neutron Source: When combined with beryllium.

💡 Fun Facts About Actinium

  • 🌟 Glows blue.
  • ⏳ Half-life of 21.8 years.
  • 🏞️ Found in uranium ores.
  • 🔢 Starts the actinide series.

⚠️ Safety & Precautions

Actinium is highly radioactive and a radiation risk. Handle with extreme care in controlled environments only.

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