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Actinium
2009-07-09 17:04:18

Actinium is a radioactive chemical element. The symbol for Actinium is Ac and the atomic number is 89. Actinium was discovered in 1899 by French chemist André-Louis Debierne. It was the first non-primordial radioactive element to be isolated. Actinium is amongst a group of 15 similar elements within the periodic table that make up the actinoid series. This substance was also independently...

Word of the Day
drawcansir
  • A blustering, bullying fellow; a pot-valiant braggart; a bully.
This word is named for Draw-Can-Sir, a character in George Villiers' 17th century play The Rehearsal.
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