The 85th Element of the Periodic Table: From the Latin route astatos By: Rachel An 8th grader at Mill Valley Middle School
	If your mad at your sibling and you want to be mean, feed them astatine
General Information Atomic Mass 210 Atomic Number 85 Common Isotopes At-210 half life 8.3 hr. common oxidation state 1 3 5 7 group/ period group 17/ period 6 The color of At is metallic black, metallic yellow and metallic green . Astatine is a solid at 298k. Astatine bolls at 337 Celsius and melts at 302 Celsius. The density is 7 grams per cubic centimeter. Neutrons: 125 Protons: 85 Electrons: 85		Take Me To: General Information History Uses Properties Glossary Bibliography
	Properties Properties the "time of Flight " mass spectrometer has been used to confirm that this highly radioactive halogen behaves chemically very much like other halogens practically Iodine. Astatine is said the be more metallic than iodine and like iodine , it accumulates in the Thyroid Gland . Workers at Brookhaven National Laboratory have recently used radioactive scattering in crossed molecular beams to identify and measure elementary reactions involving astatine.	This is how astatine appears on the Periodic Table
	Can you count how many neutrons, protons, electrons there are above?	History Astatine was synthesized in 1940 by Dr. ton, Kr. Mackenzie, and E. segr at the University of California by bombarding bismuth with alpha particles. The longest lived isotope , with naturally occurring uranium and thorium isotopes, and traces of 217 At are equilibrium with 233U and 239 NP resulting from integration of thorium and uranium with naturally produced neutrons. the total amount of astatine present in the earths crust, however is less than 1 oz.
	Uses Astatine can be produced by bombarding bismuth with energetic alpha particles to obtain the relativity long-lived 209-211 At, which can be distilled from the target by heating in air. At-85 has been used for over 25 years to measure the density of paper as it is manufactured. The total weight of paper can be controlled to a very accurate degree by the use of At-85 and other radioactive nuclides. The common use for such a device is a beta gauge that can measure the thickness of a material	One of the Uses:
	Glossary Atomic Number-- The number of protons in an atomic nucleus. Atomic Mass -- The mass of an atom, usually expressed in atomic mass units. Isotopes -- One of two or more atoms having the same atomic number but different mass numbers. Oxidation state -- The combination of a substance with oxygen. A reaction in which the atoms in an element lose electrons and the valence of the element is correspondingly increased. Neutron -- An electrically neutral subatomic particle in the baryon family, having a mass 1,839 times that of the electron, stable when bound in an atomic nucleus, and having a mean lifetime of approximately 1.0 ¥ 103 seconds as a free particle. It and the proton form nearly the entire mass of atomic nuclei. See table at subatomic particle. Proton -- A stable, positively charged subatomic particle in the baryon family having a mass 1,836 times that of the electron. See table at subatomic particle. Electrons -- A stable subatomic particle in the lepton family having a rest mass of 9.1066 ¥ 10-28 grams and a unit negative electric charge of approximately 1.602 ¥ 10-19 coulombs. See table at subatomic particle. Synthesized -- To combine so as to form a new, complex product: "His works synthesize photography, painting and linguistic devices" (Paul Taylor). To form or produce by chemical synthesis. Alpha Particle -- A positively charged particle, indistinguishable from a helium atom nucleus and consisting of two protons and two neutrons. Uranium -- A heavy silvery-white metallic element, radioactive and toxic, easily oxidized, and having 14 known isotopes of which U 238 is the most abundant in nature. The element occurs in several minerals, including carnotite, from which it is extracted and processed for use in research, nuclear fuels, and nuclear weapons. Atomic number 92; atomic weight 238.03; melting point 1,132°C; boiling point 3,818°C; specific gravity 18.95; valence 2, 3, 4, 5, 6. Isotopes -- One of two or more atoms having the same atomic number but different mass numbers. Bismuth -- A white, crystalline, brittle, highly diamagnetic metallic element used in alloys to form sharp castings for objects sensitive to high temperatures and in various low-melting alloys for fire-safety devices. Atomic number 83; atomic weight 208.98; melting point 271.3°C; boiling point 1,560°C; specific gravity 9.747; valence 3, 5. Distilled -- To separate or extract the essential elements of Halogen -- Any of a group of five chemically related nonmetallic elements including fluorine, chlorine, bromine, iodine, and astatine.   For more definitions go to: Dictionary. com
	Bibliography   *Chemicool Periodic Table *Interactive Periodic Table of the Elements *Periodic Table of the Elements *Pictorial Periodic Table   *Images found at: http://www.pmsd.k12.pa.us/.../ptable/ g83/Astatine/Astatine.html http://images.google.com/imgres?imgurl=www.chemicalelements.com/bohr/b0085.gif