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Astatine Essay Emmett Astatine Essay Division 3X April 30,2019 Astatine Astatine is a non-metal that only small amounts have ever been produced. The atomic symbol for Astatine is At, has an atomic number of 85, and an atomic mass of 210 amu. Because so little of this particular element has been created, not much is known about its physical characteristics. However, we do know that it contains 85 protons and 125 neutrons. Astatine is a very toxic element due to its radioactivity. Astatine has a melting point of 302.0 °C and a boiling point of 337.0 °C. Because of the miniscule amount of astatine ever produced, there are no known uses of the element outside of research. The discovery of Astatine has had a long and complex history. In 1869, Mendeleev created his first periodic table. He noticed that there was a space directly under iodine, and he needed to figure out what that element was since it had not been discovered yet. In 1940, a group of chemists from the University of California Berklee. Using a Cyclotron, a form of particle accelerator created by Ernest O. Lawrence, the group bombarded the element Bismuth-209 with Alpha particles. By doing this, the scientists created the first physical example of Astatine. Because of its lack of stability and radioactivity, Astatine only has a half life of 8 hours. In the mid 1940’s, scientists Berta Karlik and Traude Bernet were able to find examples of Astatine in nature as a result of studying radioactive decay. It was discovered that Astatine appears naturally in both Uranium and Thorium minerals. Despite this, very little is still known about the element, as only 25 grams of Astatine exists naturally on the planet. Because Astatine is a halogen and a nonmetal, scientists predict that Astatine performs similar to other halogens, and is predicted to form salt when reacting with metals. The common bond of Astatine is Xenon, a noble gas that is found in the Earth's Atmosphere. Astatine has come up a lot in modern times due to medical scientists predicting that Astatine could be used as a form of treatment for cancer patients. One of the strands of Astatine known as Astatine-209, has enough radioactivity to destroy cells when decayed. Francois Guerard, a chemist who works in Nuclear cancer treatments, wrote in an article on the uses of the element, saying: “Using radioactive isotopes to eradicate tumors is nothing new: therapies relying on this approach already exist. However, available treatments involve the use of radioactive elements, which emit “beta” particles that penetrate a few millimeters into biological tissues. Although they can be helpful for the treatment of large-sized tumors (several millimeters in diameter), these particles have proved ineffective when targeting those smaller than a millimeter, as they also destroy the healthy tissue around the tumor. On the other hand, astatine-211 emits “alpha” particles whose low penetration into matter (the thickness of a sheet of paper, or just 3 to 4 cells), could make it possible to treat isolated cancer cells (for example, in the case of leukemia) or small tumors such as disseminated micrometastases, and supplement conventional therapies (chemotherapy or surgery) after which undetectable tumor residues may persist and lead to a recurrence.” Electron Configuration: [Xe] 4f 145d 106s 2 6p 5 .
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