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WS Element of Month Fluorine Final V2 All About Elements: Fluorine 1 Ward’s All About Elements Series Building Real-World Connections to the Building Blocks of Chemistry PERIODIC TABLE OF THE ELEMENTS GROUP 1/IA 18/VIIIA 1 2 H KEY He Atomic Number 1.01 2/IIA 35 13/IIIA 14/IVA 15/VA 16/VIA 17/VIIA 4.00 3 4 5 6 7 8 9 10 Li Be Symbol Br B C N O F Ne 6.94 9.01 79.90 Atomic Weight 10.81 12.01 14.01 16.00 19.00 20.18 11 12 13 14 15 16 17 18 Na Mg Al Si P S Cl Ar 8 9 10 22.99 24.31 3/IIIB 4/IVB 5/VB 6/VIB 7/VIIB VIIIBVIII 11/IB 12/IIB 26.98 28.09 30.97 32.07 35.45 39.95 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr 39.10 40.08 44.96 47.87 50.94 52.00 54.94 55.85 58.93 58.69 63.55 65.41 69.72 72.64 74.92 78.9678.96 79.90 83.80 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe 85.47 87.62 88.91 91.22 92.91 95.94 (97.91)(98) 101.07 102.91 106.42 107.87 112.41 114.82 118.71 121.76 127.60 126.90 131.29 55 56 57–71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 Cs Ba La-Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn ´ 132.91 137.33 178.49 180.95 183.84 186.21 190.23 192.22 195.08 196.97 200.59 204.38 207.20207.2 208.98 (208.98)(209) (209.99)(210) (222.02)(222) 87 88 89–103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 Fr Ra AcAc-Lr - Lr Rf Db Sg Bh Hs Mt Ds Rg Uub Uut Uuq Uup Uuh Uus Uuo ´´ (223.02)(223) (226.03)(226) (261.11)(261) (262.11)(262) (266.12)(266) (264.12)(264) (277.00)(277) (268.14)(268) (247.07)(269) (280.00)(272) (285.00)(285) (284.00)(284) (289.00)(289) (288.00)(288) (293.00)(289) (294.00) (294.00)(294) ´ 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu 138.91 140.12 140.91 144.24 (144.91)(145) 150.36 151.97151.96 157.25 158.93 162.50 164.93 167.26 168.93 173.04 174.97 US: www.wardsci.com Canada: www.wardsci.ca ´´ 800-962-2660 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 © 2010 Rev. 7/15 Ward’s Science. All Rights Reserved. No portion of this work may be reproduced in any form Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr or by any means without express prior written permission from Ward’s Science. (227.03)(227) 232.04232.04 231.04 238.03 (237.05)(237) (244.06)(244) (243.06)(243) (247.07)(247) (247.07)(247) (251.08)(251) (252.08)(252) (257.10)(257) (258.10)(258) (259.10)(259) (262.11)(262) US: www.scholarchemistry.com Canada: www.scholarchemistry.ca NOTES: Black — solid Red — gas Blue — liquid — synthetically prepared 866-260-0501 © Copyright 2010 ScholAR Chemistry. All Rights Reserved. Values provided are based on the 85th edition of the CRC Handbook of Chemistry and Physics. Some values have been rounded. BASICNo portion PERIODIC of this work TABLE may be reproduced- SIDE 1 (Rev.in any form7/15) or by any means without express prior written permission from ScholAR Chemistry. Catalog #9630200 The periodic table of elements is an essential part of any chemistry classroom or science lab, but have you ever stopped to wonder about all of the amazing ways each element is used to create the world around us? Each of the trillions of substances in our universe can be tied back to just these 118 simple, yet powerful elements. In our All About Elements series, we’ve brought together the most fascinating facts and figures about your favorite elements so students can explore their properties and uses in the real world and you can create chemistry connections in your classroom and beyond. Look for a new featured element each month, plus limited-time savings on select hands-on materials to incorporate these element in your lessons. FollowFacebook “f” Logo usCMYK / .eps Facebook “f”on: Logo CMYKOR / .eps Sign up to receive Ward’s Science emails at wardsci.com and get a new element in your inbox each month. Check back often at wardsci.com/elements for the latest content and exclusive savings on new teaching tools each month. wardsci.com | 800-962-2660 2 Fun Facts About… 9 Fluorine 1. Fluorine has both toxic and helpful proper- ties that make it widely used, from medical treatments to poisonous gases and nuclear applications. 2. Fluorine gets its name from the Latin word “fleure” which means “to flow”, which is what fluorine allows metals to do. 1 F 3. Although the element fluorine was known 19.00 to exist in 1813, it wasn’t until 1886 that Henri Moissan was able to isolate the ele- ment after numerous failed, and sickening, attempts. 4. Fluorine wasn’t mass produced until it was needed for nuclear applications during World War II. 5. One of the reasons you’ve probably had only a cavity or two is due to the fluoridation of water, which was first tested in 1944 in Grand Rapids Michigan. Here it was determined that fluoride helped strengthen teeth. All About Fluorine: Fluorine is the ninth element on the periodic table found in group 17 (7A) with an atomic number of 9 and a symbol F. Fluorine gets its name from the Latin word “fleure” which means “to flow”, which is what fluorine allowed metals to do. 1 Fluorine came also from the “fluor” in fluorspar (which we now know to be calcium fluoride.)1 Group 17 is known as the halogens and fluorine is known to be the most reactive of all of the halogens, gaining one electron in most cases to become a stable fluoride ion. Fluorine is the smallest of the halogens with an electron configuration of 1s22s22p5, and has both the highest ionization energy in its group and the highest electro- negativity on the periodic table. Fluorine has a density of 1.696 grams per liter which is the lowest density of all of the elements in its group and is the second least dense gas, behind neon with a density of 0.9 g/L, in its period on the periodic table. 4 Before fluorine was isolated in 1886, it was known to exist in a number of compounds.1 These compounds are where you will find fluorine most of the time today, as diatomic elemental fluorine doesn’t exist in nature, but rather must be created by electrolysis. Some of the more common compounds of fluorine are fluorspar, hydrofluoric acid, potassium fluoride, sodium fluoride, tin (II) fluoride, sodium monofluorophosphate, uranium hexafluoride, dichlorodifluoromethane, and polytetrafluoroethylene.5 These compounds range in use from additives to toothpaste for strength- ening teeth, to use in atomic bombs for their explosive nature. Fluorine has also been found to react with the noble gases xenon, krypton and radon despite their full octet of electrons. 6 Although it is found in these and other compounds, fluorine typically only has an oxidation state of -1 due to its high electronegativity. In addition, there is only one stable isotope of fluorine, F-19 with 9 protons and 10 neutrons.5 3 Properties of Fluorine In its pure gaseous state, fluorine is pale yellow and extremely corrosive reacting with most organic and inorganic substances.6 Specifically, fluorine’s color can only be seen by looking down at it through a test tube, not from the side.18 In addition, it can be lethal and will react with glass, ceramics, carbon, finely divided metals and even water to create an explosion.6 Because of its explosive nature, it is commonly shipped as a cryogenic liquid.10 If fluorine is inhaled or absorbed through the skin it is toxic, but even at lower than lethal concentrations it can cause chemical burns.10 Some of these properties have been put to good use, as hydrofluoric acid is used to etch glass, something that is a delicate process. Even though fluorine is found in trace amounts on Earth (it is the 13th most common element in Earth’s crust,11 and only amounts to 1.3 milligrams per liter in the ocean5) and in the universe, it is most commonly found in the form of a fluoride ion. For instance, the fluoride ion is present at about 3 ppm in the human body!7 Compounds that are added to toothpaste and drinking water are all in the form of the ion, not the toxic gas. All of the stable naturally occurring fluorine is F-19, with isotopes used for a variety of medical purposes and having a variety of half lives.
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