Upper Limit of the Periodic Table and the Future Superheavy Elements
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10 NYCRR Part 16 Appendix a on Exemptions
APPENDIX 16-A TABLE 1 EXEMPTIONS Table 1-A. Radioactive Materials Item (a) Exempt concentrations. (1) Except as provided in paragraph (2) of this item, any person is exempt from the requirements of this Part to the extent that such person transfers, receives, possesses or uses products or materials containing radioactive material in concentrations not in excess of those listed in Table 2 of this Appendix. (2) No person may introduce radioactive material into a product or material knowing or having reason to believe that it will be transferred to persons exempt under paragraph (1) of this item or equivalent regulations of the United States Nuclear Regulatory Commission or any agreement State, except in accordance with specific license issued by the department or a similar license issued by the State Department of Labor, the New York City Department of Health, the United States Nuclear Regulatory Commission, any agreement State or the general license provided in item (h) of Table 6 of this Appendix. Item (b) Exempt quantities.1 (1) Except as provided in paragraphs (2) and (3) of this item, any person is exempt from the requirements of this Part to the extent that such person transfers, receives, possesses or uses radioactive material in individual quantities each of which does not exceed the applicable quantity set forth in Table 3 of this Appendix. (2) Any person who possesses radioactive material received prior to July 1, 1973, under the exemption formerly provided in section 16.101 of this Part is exempt from the requirements of this Part to the extent that such person transfers, receives, possesses or uses such radioactive material. -
5 Heavy Metals As Endocrine-Disrupting Chemicals
5 Heavy Metals as Endocrine-Disrupting Chemicals Cheryl A. Dyer, PHD CONTENTS 1 Introduction 2 Arsenic 3 Cadmium 4 Lead 5 Mercury 6 Uranium 7 Conclusions 1. INTRODUCTION Heavy metals are present in our environment as they formed during the earth’s birth. Their increased dispersal is a function of their usefulness during our growing dependence on industrial modification and manipulation of our environment (1,2). There is no consensus chemical definition of a heavy metal. Within the periodic table, they comprise a block of all the metals in Groups 3–16 that are in periods 4 and greater. These elements acquired the name heavy metals because they all have high densities, >5 g/cm3 (2). Their role as putative endocrine-disrupting chemicals is due to their chemistry and not their density. Their popular use in our industrial world is due to their physical, chemical, or in the case of uranium, radioactive properties. Because of the reactivity of heavy metals, small or trace amounts of elements such as iron, copper, manganese, and zinc are important in biologic processes, but at higher concentrations they often are toxic. Previous studies have demonstrated that some organic molecules, predominantly those containing phenolic or ring structures, may exhibit estrogenic mimicry through actions on the estrogen receptor. These xenoestrogens typically are non-steroidal organic chemicals released into the environment through agricultural spraying, indus- trial activities, urban waste and/or consumer products that include organochlorine pesticides, polychlorinated biphenyls, bisphenol A, phthalates, alkylphenols, and parabens (1). This definition of xenoestrogens needs to be extended, as recent investi- gations have yielded the paradoxical observation that heavy metals mimic the biologic From: Endocrine-Disrupting Chemicals: From Basic Research to Clinical Practice Edited by: A. -
Lanthanides & Actinides Notes
- 1 - LANTHANIDES & ACTINIDES NOTES General Background Mnemonics Lanthanides Lanthanide Chemistry Presents No Problems Since Everyone Goes To Doctor Heyes' Excruciatingly Thorough Yearly Lectures La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Actinides Although Theorists Prefer Unusual New Proofs Able Chemists Believe Careful Experiments Find More New Laws Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr Principal Characteristics of the Rare Earth Elements 1. Occur together in nature, in minerals, e.g. monazite (a mixed rare earth phosphate). 2. Very similar chemical properties. Found combined with non-metals largely in the 3+ oxidation state, with little tendency to variable valence. 3. Small difference in solubility / complex formation etc. of M3+ are due to size effects. Traversing the series r(M3+) steadily decreases – the lanthanide contraction. Difficult to separate and differentiate, e.g. in 1911 James performed 15000 recrystallisations to get pure Tm(BrO3)3! f-Orbitals The Effective Electron Potential: • Large angular momentum for an f-orbital (l = 3). • Large centrifugal potential tends to keep the electron away from the nucleus. o Aufbau order. • Increased Z increases Coulombic attraction to a larger extent for smaller n due to a proportionately greater change in Zeff. o Reasserts Hydrogenic order. This can be viewed empirically as due to differing penetration effects. Radial Wavefunctions Pn,l2 for 4f, 5d, 6s in Ce 4f orbitals (and the atoms in general) steadily contract across the lanthanide series. Effective electron potential for the excited states of Ba {[Xe] 6s 4f} & La {[Xe] 6s 5d 4f} show a sudden change in the broadness & depth of the 4f "inner well". -
Table 2.Iii.1. Fissionable Isotopes1
FISSIONABLE ISOTOPES Charles P. Blair Last revised: 2012 “While several isotopes are theoretically fissionable, RANNSAD defines fissionable isotopes as either uranium-233 or 235; plutonium 238, 239, 240, 241, or 242, or Americium-241. See, Ackerman, Asal, Bale, Blair and Rethemeyer, Anatomizing Radiological and Nuclear Non-State Adversaries: Identifying the Adversary, p. 99-101, footnote #10, TABLE 2.III.1. FISSIONABLE ISOTOPES1 Isotope Availability Possible Fission Bare Critical Weapon-types mass2 Uranium-233 MEDIUM: DOE reportedly stores Gun-type or implosion-type 15 kg more than one metric ton of U- 233.3 Uranium-235 HIGH: As of 2007, 1700 metric Gun-type or implosion-type 50 kg tons of HEU existed globally, in both civilian and military stocks.4 Plutonium- HIGH: A separated global stock of Implosion 10 kg 238 plutonium, both civilian and military, of over 500 tons.5 Implosion 10 kg Plutonium- Produced in military and civilian 239 reactor fuels. Typically, reactor Plutonium- grade plutonium (RGP) consists Implosion 40 kg 240 of roughly 60 percent plutonium- Plutonium- 239, 25 percent plutonium-240, Implosion 10-13 kg nine percent plutonium-241, five 241 percent plutonium-242 and one Plutonium- percent plutonium-2386 (these Implosion 89 -100 kg 242 percentages are influenced by how long the fuel is irradiated in the reactor).7 1 This table is drawn, in part, from Charles P. Blair, “Jihadists and Nuclear Weapons,” in Gary A. Ackerman and Jeremy Tamsett, ed., Jihadists and Weapons of Mass Destruction: A Growing Threat (New York: Taylor and Francis, 2009), pp. 196-197. See also, David Albright N 2 “Bare critical mass” refers to the absence of an initiator or a reflector. -
The Periodic Electronegativity Table
The Periodic Electronegativity Table Jan C. A. Boeyens Unit for Advanced Study, University of Pretoria, South Africa Reprint requests to J. C. A. Boeyens. E-mail: [email protected] Z. Naturforsch. 2008, 63b, 199 – 209; received October 16, 2007 The origins and development of the electronegativity concept as an empirical construct are briefly examined, emphasizing the confusion that exists over the appropriate units in which to express this quantity. It is shown how to relate the most reliable of the empirical scales to the theoretical definition of electronegativity in terms of the quantum potential and ionization radius of the atomic valence state. The theory reflects not only the periodicity of the empirical scales, but also accounts for the related thermochemical data and serves as a basis for the calculation of interatomic interaction within molecules. The intuitive theory that relates electronegativity to the average of ionization energy and electron affinity is elucidated for the first time and used to estimate the electron affinities of those elements for which no experimental measurement is possible. Key words: Valence State, Quantum Potential, Ionization Radius Introduction electronegative elements used to be distinguished tra- ditionally [1]. Electronegativity, apart from being the most useful This theoretical notion, in one form or the other, has theoretical concept that guides the practising chemist, survived into the present, where, as will be shown, it is also the most bothersome to quantify from first prin- provides a precise definition of electronegativity. Elec- ciples. In historical context the concept developed in a tronegativity scales that fail to reflect the periodicity of natural way from the early distinction between antag- the L-M curve will be considered inappropriate. -
NOBELIUM Element Symbol: No Atomic Number: 102
NOBELIUM Element Symbol: No Atomic Number: 102 An initiative of IYC 2011 brought to you by the RACI KERRY LAMB www.raci.org.au NOBELIUM Element symbol: No Atomic number: 102 The credit for discovering Nobelium was disputed with 3 different research teams claiming the discovery. While the first claim dates back to 1957, it was not until 1992 that the International Union of Pure and Applied Chemistry credited the discovery to a research team from Dubna in Russia for work they did in 1966. The element was named Nobelium in 1957 by the first of its claimed discoverers (the Nobel Institute in Sweden). It was named after Alfred Nobel, a Swedish chemist who invented dynamite, held more than 350 patents and bequeathed his fortune to the establishment of the Nobel Prizes. Nobelium is a synthetic element and does not occur in nature and has no known uses other than in scientific research as only tiny amounts of the element have ever been produced. Nobelium is radioactive and most likely metallic. The appearance and properties of Nobelium are unknown as insufficient amounts of the element have been produced. Nobelium is made by the bombardment of curium (Cm) with carbon nuclei. Its most stable isotope, 259No, has a half-life of 58 minutes and decays to Fermium (255Fm) through alpha decay or to Mendelevium (259Md) through electron capture. Provided by the element sponsor Freehills Patent and Trade Mark Attorneys ARTISTS DESCRIPTION I wanted to depict Alfred Nobel, the namesake of Nobelium, as a resolute young man, wearing the Laurel wreath which is the symbol of victory. -
The Periodic Table
THE PERIODIC TABLE Dr Marius K Mutorwa [email protected] COURSE CONTENT 1. History of the atom 2. Sub-atomic Particles protons, electrons and neutrons 3. Atomic number and Mass number 4. Isotopes and Ions 5. Periodic Table Groups and Periods 6. Properties of metals and non-metals 7. Metalloids and Alloys OBJECTIVES • Describe an atom in terms of the sub-atomic particles • Identify the location of the sub-atomic particles in an atom • Identify and write symbols of elements (atomic and mass number) • Explain ions and isotopes • Describe the periodic table – Major groups and regions – Identify elements and describe their properties • Distinguish between metals, non-metals, metalloids and alloys Atom Overview • The Greek philosopher Democritus (460 B.C. – 370 B.C.) was among the first to suggest the existence of atoms (from the Greek word “atomos”) – He believed that atoms were indivisible and indestructible – His ideas did agree with later scientific theory, but did not explain chemical behavior, and was not based on the scientific method – but just philosophy John Dalton(1766-1844) In 1803, he proposed : 1. All matter is composed of atoms. 2. Atoms cannot be created or destroyed. 3. All the atoms of an element are identical. 4. The atoms of different elements are different. 5. When chemical reactions take place, atoms of different elements join together to form compounds. J.J.Thomson (1856-1940) 1. Proposed the first model of the atom. 2. 1897- Thomson discovered the electron (negatively- charged) – cathode rays 3. Thomson suggested that an atom is a positively- charged sphere with electrons embedded in it. -
Historical Development of the Periodic Classification of the Chemical Elements
THE HISTORICAL DEVELOPMENT OF THE PERIODIC CLASSIFICATION OF THE CHEMICAL ELEMENTS by RONALD LEE FFISTER B. S., Kansas State University, 1962 A MASTER'S REPORT submitted in partial fulfillment of the requirements for the degree FASTER OF SCIENCE Department of Physical Science KANSAS STATE UNIVERSITY Manhattan, Kansas 196A Approved by: Major PrafeLoor ii |c/ TABLE OF CONTENTS t<y THE PROBLEM AND DEFINITION 0? TEH-IS USED 1 The Problem 1 Statement of the Problem 1 Importance of the Study 1 Definition of Terms Used 2 Atomic Number 2 Atomic Weight 2 Element 2 Periodic Classification 2 Periodic Lav • • 3 BRIEF RtiVJiM OF THE LITERATURE 3 Books .3 Other References. .A BACKGROUND HISTORY A Purpose A Early Attempts at Classification A Early "Elements" A Attempts by Aristotle 6 Other Attempts 7 DOBEREBIER'S TRIADS AND SUBSEQUENT INVESTIGATIONS. 8 The Triad Theory of Dobereiner 10 Investigations by Others. ... .10 Dumas 10 Pettehkofer 10 Odling 11 iii TEE TELLURIC EELIX OF DE CHANCOURTOIS H Development of the Telluric Helix 11 Acceptance of the Helix 12 NEWLANDS' LAW OF THE OCTAVES 12 Newlands' Chemical Background 12 The Law of the Octaves. .........' 13 Acceptance and Significance of Newlands' Work 15 THE CONTRIBUTIONS OF LOTHAR MEYER ' 16 Chemical Background of Meyer 16 Lothar Meyer's Arrangement of the Elements. 17 THE WORK OF MENDELEEV AND ITS CONSEQUENCES 19 Mendeleev's Scientific Background .19 Development of the Periodic Law . .19 Significance of Mendeleev's Table 21 Atomic Weight Corrections. 21 Prediction of Hew Elements . .22 Influence -
The Development of the Periodic Table and Its Consequences Citation: J
Firenze University Press www.fupress.com/substantia The Development of the Periodic Table and its Consequences Citation: J. Emsley (2019) The Devel- opment of the Periodic Table and its Consequences. Substantia 3(2) Suppl. 5: 15-27. doi: 10.13128/Substantia-297 John Emsley Copyright: © 2019 J. Emsley. This is Alameda Lodge, 23a Alameda Road, Ampthill, MK45 2LA, UK an open access, peer-reviewed article E-mail: [email protected] published by Firenze University Press (http://www.fupress.com/substantia) and distributed under the terms of the Abstract. Chemistry is fortunate among the sciences in having an icon that is instant- Creative Commons Attribution License, ly recognisable around the world: the periodic table. The United Nations has deemed which permits unrestricted use, distri- 2019 to be the International Year of the Periodic Table, in commemoration of the 150th bution, and reproduction in any medi- anniversary of the first paper in which it appeared. That had been written by a Russian um, provided the original author and chemist, Dmitri Mendeleev, and was published in May 1869. Since then, there have source are credited. been many versions of the table, but one format has come to be the most widely used Data Availability Statement: All rel- and is to be seen everywhere. The route to this preferred form of the table makes an evant data are within the paper and its interesting story. Supporting Information files. Keywords. Periodic table, Mendeleev, Newlands, Deming, Seaborg. Competing Interests: The Author(s) declare(s) no conflict of interest. INTRODUCTION There are hundreds of periodic tables but the one that is widely repro- duced has the approval of the International Union of Pure and Applied Chemistry (IUPAC) and is shown in Fig.1. -
The Periodic Table of Elements
The Periodic Table of Elements 1 2 6 Atomic Number = Number of Protons = Number of Electrons HYDROGENH HELIUMHe 1 Chemical Symbol NON-METALS 4 3 4 C 5 6 7 8 9 10 Li Be CARBON Chemical Name B C N O F Ne LITHIUM BERYLLIUM = Number of Protons + Number of Neutrons* BORON CARBON NITROGEN OXYGEN FLUORINE NEON 7 9 12 Atomic Weight 11 12 14 16 19 20 11 12 13 14 15 16 17 18 SODIUMNa MAGNESIUMMg ALUMINUMAl SILICONSi PHOSPHORUSP SULFURS CHLORINECl ARGONAr 23 24 METALS 27 28 31 32 35 40 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 POTASSIUMK CALCIUMCa SCANDIUMSc TITANIUMTi VANADIUMV CHROMIUMCr MANGANESEMn FeIRON COBALTCo NICKELNi CuCOPPER ZnZINC GALLIUMGa GERMANIUMGe ARSENICAs SELENIUMSe BROMINEBr KRYPTONKr 39 40 45 48 51 52 55 56 59 59 64 65 70 73 75 79 80 84 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 RUBIDIUMRb STRONTIUMSr YTTRIUMY ZIRCONIUMZr NIOBIUMNb MOLYBDENUMMo TECHNETIUMTc RUTHENIUMRu RHODIUMRh PALLADIUMPd AgSILVER CADMIUMCd INDIUMIn SnTIN ANTIMONYSb TELLURIUMTe IODINEI XeXENON 85 88 89 91 93 96 98 101 103 106 108 112 115 119 122 128 127 131 55 56 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 CESIUMCs BARIUMBa HAFNIUMHf TANTALUMTa TUNGSTENW RHENIUMRe OSMIUMOs IRIDIUMIr PLATINUMPt AuGOLD MERCURYHg THALLIUMTl PbLEAD BISMUTHBi POLONIUMPo ASTATINEAt RnRADON 133 137 178 181 184 186 190 192 195 197 201 204 207 209 209 210 222 87 88 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 FRANCIUMFr RADIUMRa RUTHERFORDIUMRf DUBNIUMDb SEABORGIUMSg BOHRIUMBh HASSIUMHs MEITNERIUMMt DARMSTADTIUMDs ROENTGENIUMRg COPERNICIUMCn NIHONIUMNh -
TEK 8.5C: Periodic Table
Name: Teacher: Pd. Date: TEK 8.5C: Periodic Table TEK 8.5C: Interpret the arrangement of the Periodic Table, including groups and periods, to explain how properties are used to classify elements. Elements and the Periodic Table An element is a substance that cannot be separated into simpler substances by physical or chemical means. An element is already in its simplest form. The smallest piece of an element that still has the properties of that element is called an atom. An element is a pure substance, containing only one kind of atom. The Periodic Table of Elements is a list of all the elements that have been discovered and named, with each element listed in its own element square. Elements are represented on the Periodic Table by a one or two letter symbol, and its name, atomic number and atomic mass. The Periodic Table & Atomic Structure The elements are listed on the Periodic Table in atomic number order, starting at the upper left corner and then moving from the left to right and top to bottom, just as the words of a paragraph are read. The element’s atomic number is based on the number of protons in each atom of that element. In electrically neutral atoms, the atomic number also represents the number of electrons in each atom of that element. For example, the atomic number for neon (Ne) is 10, which means that each atom of neon has 10 protons and 10 electrons. Magnesium (Mg) has an atomic number of 12, which means it has 12 protons and 12 electrons. -
Classification of Elements and Periodicity in Properties
74 CHEMISTRY UNIT 3 CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIES The Periodic Table is arguably the most important concept in chemistry, both in principle and in practice. It is the everyday support for students, it suggests new avenues of research to After studying this Unit, you will be professionals, and it provides a succinct organization of the able to whole of chemistry. It is a remarkable demonstration of the fact that the chemical elements are not a random cluster of • appreciate how the concept of entities but instead display trends and lie together in families. grouping elements in accordance to An awareness of the Periodic Table is essential to anyone who their properties led to the wishes to disentangle the world and see how it is built up development of Periodic Table. from the fundamental building blocks of the chemistry, the understand the Periodic Law; • chemical elements. • understand the significance of atomic number and electronic Glenn T. Seaborg configuration as the basis for periodic classification; • name the elements with In this Unit, we will study the historical development of the Z >100 according to IUPAC Periodic Table as it stands today and the Modern Periodic nomenclature; Law. We will also learn how the periodic classification • classify elements into s, p, d, f follows as a logical consequence of the electronic blocks and learn their main configuration of atoms. Finally, we shall examine some of characteristics; the periodic trends in the physical and chemical properties • recognise the periodic trends in of the elements. physical and chemical properties of elements; 3.1 WHY DO WE NEED TO CLASSIFY ELEMENTS ? compare the reactivity of elements • We know by now that the elements are the basic units of all and correlate it with their occurrence in nature; types of matter.