Astatine
AS-teh-teen
Astatine (At) is a radioactive non-metal that has the atomic number 85 in the periodic table in Group 17. It has the symbol At.
Astatine is classed as a halogen and a non metal. It was predicted to exist by Mendeleev and he called it eka-iodine. Astatine however could not be found in nature but was made in the lab in 1940. It was made by Dale Coson, Kenneth Ross Mackenzie and Emilio Segrè by bombarding bismuth with alpha particles. It is very unstable and breaks down quickly. Its uses are in cancer treatment and as a tracer due to its very short half life. It is a solid non metal at room temperature with a melting point of 302°c and a boiling point of 336°c. Astatine like Iodine can be absorbed by the thyroid, in animal studies due to its radioactivity it was discovered that this causes greater damage that iodine due to astatine being easily absorbed by animal thyroids.
FAQ's
D.R.Corson, K.R.MacKenzie, E.Segré
1940
Uses
Since its isotopes have such short half-lives there are no commercially significant compounds of astatine.
Sources
Does not occur in nature. Similar to iodine. Produced by bombarding bismuth with alpha particles.
About the author
Nathan M
Nathan has a degree in BSc Biomedical Chemistry at Warwick University and a degree in PGCE Science at Wolverhampton University, UK. Nathan's subject matter ranges from general chemistry and organic chemistry. Nathan also created the curriculum on Breaking Atom in the course page.
Citation
At
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