Periodic Table 1 Periodic Table
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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". -
Evolution and Understanding of the D-Block Elements in the Periodic Table Cite This: Dalton Trans., 2019, 48, 9408 Edwin C
Dalton Transactions View Article Online PERSPECTIVE View Journal | View Issue Evolution and understanding of the d-block elements in the periodic table Cite this: Dalton Trans., 2019, 48, 9408 Edwin C. Constable Received 20th February 2019, The d-block elements have played an essential role in the development of our present understanding of Accepted 6th March 2019 chemistry and in the evolution of the periodic table. On the occasion of the sesquicentenniel of the dis- DOI: 10.1039/c9dt00765b covery of the periodic table by Mendeleev, it is appropriate to look at how these metals have influenced rsc.li/dalton our understanding of periodicity and the relationships between elements. Introduction and periodic tables concerning objects as diverse as fruit, veg- etables, beer, cartoon characters, and superheroes abound in In the year 2019 we celebrate the sesquicentennial of the publi- our connected world.7 Creative Commons Attribution-NonCommercial 3.0 Unported Licence. cation of the first modern form of the periodic table by In the commonly encountered medium or long forms of Mendeleev (alternatively transliterated as Mendelejew, the periodic table, the central portion is occupied by the Mendelejeff, Mendeléeff, and Mendeléyev from the Cyrillic d-block elements, commonly known as the transition elements ).1 The periodic table lies at the core of our under- or transition metals. These elements have played a critical rôle standing of the properties of, and the relationships between, in our understanding of modern chemistry and have proved to the 118 elements currently known (Fig. 1).2 A chemist can look be the touchstones for many theories of valence and bonding. -
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. -
1201: Introduction to Aluminium As an Engineering Material
TALAT Lecture 1201 Introduction to Aluminium as an Engineering Material 23 pages, 26 figures (also available as overheads) Basic Level prepared by M H Jacobs * Interdisciplinary Research Centre in Materials The University of Birmingham, UK Objectives To provide an introduction to metallurgical concepts necessary to understand how structural features of aluminium alloys are influenced by alloy composition, processing and heat treatment, and the basic affects of these parameters on the mechanical properties, and hence engineering applications, of the alloys. It is assumed that the reader has some elementary knowledge of physics, chemistry and mathematics. Date of Issue: 1999 EAA - European Aluminium Association 1201 Introduction to Aluminium as an Engineering Material Contents (26 figures) 1201 Introduction to Aluminium as an Engineering Material _____________________ 2 1201.01. Basic mechanical and physical properties__________________________________ 3 1201.01.01 Background _______________________________________________________________ 3 1201.01.02 Commercially pure aluminium ______________________________________________ 4 1201.02 Crystal structure and defects _____________________________________________ 6 1201.02.01 Crystals and atomic bonding __________________________________________________ 6 1201.02.02 Atomic structure of aluminium ______________________________________________ 8 1201.02.03 Crystal structures _________________________________________________________ 8 1201.02.04 Some comments on crystal structures of materials -
IA Metals: Alkali Metals
IA Metals: Alkali Metals INTRODUCTION: The alkali metals are a group in the periodic table consisting of the chemical elements lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs). You should remember that there is a separate group called the alkaline earth metals in Group Two. They are a very different family, even though they have a similar name. The seventh member of alkali metals group – francium, is radioactive and so rare that only 20 atoms of francium may exist on Earth at any given moment. The term alkali is derived from an Arabic word meaning “ashes.” PHYSICAL PROPERTIES: Shiny Soft (They can all be cut easily with a knife ) Highly reactive at standard temperature and pressure Because of their high reactivity, they must be stored under oil to prevent reaction with air Their density increases as we move from Li to F White/metal coloured Very good conductors of heat and electricity Have the ability to impart colour to the flame. This property of alkali metals is used in their identification. CHEMICAL PROPERTIES: The atom of any given alkali metal has only one valence electron. The chemical reactivity of alkali metals increase as we move from the top to the bottom of the group. Like any other metals, ionization potential is very low. In fact, alkali metals have the lowest ionization potential among the elements of any given period of the periodic table. Any alkali metal when comes in contact with air or oxygen, starts burning and oxides are formed in the process. At the end of the chemical reaction, lithium gives lithium monoxide (LiO), sodium gives sodium peroxide (Na2O2) and other alkali metals give superoxides. -
An Alternate Graphical Representation of Periodic Table of Chemical Elements Mohd Abubakr1, Microsoft India (R&D) Pvt
An Alternate Graphical Representation of Periodic table of Chemical Elements Mohd Abubakr1, Microsoft India (R&D) Pvt. Ltd, Hyderabad, India. [email protected] Abstract Periodic table of chemical elements symbolizes an elegant graphical representation of symmetry at atomic level and provides an overview on arrangement of electrons. It started merely as tabular representation of chemical elements, later got strengthened with quantum mechanical description of atomic structure and recent studies have revealed that periodic table can be formulated using SO(4,2) SU(2) group. IUPAC, the governing body in Chemistry, doesn‟t approve any periodic table as a standard periodic table. The only specific recommendation provided by IUPAC is that the periodic table should follow the 1 to 18 group numbering. In this technical paper, we describe a new graphical representation of periodic table, referred as „Circular form of Periodic table‟. The advantages of circular form of periodic table over other representations are discussed along with a brief discussion on history of periodic tables. 1. Introduction The profoundness of inherent symmetry in nature can be seen at different depths of atomic scales. Periodic table symbolizes one such elegant symmetry existing within the atomic structure of chemical elements. This so called „symmetry‟ within the atomic structures has been widely studied from different prospects and over the last hundreds years more than 700 different graphical representations of Periodic tables have emerged [1]. Each graphical representation of chemical elements attempted to portray certain symmetries in form of columns, rows, spirals, dimensions etc. Out of all the graphical representations, the rectangular form of periodic table (also referred as Long form of periodic table or Modern periodic table) has gained wide acceptance. -
Suppression Mechanisms of Alkali Metal Compounds
SUPPRESSION MECHANISMS OF ALKALI METAL COMPOUNDS Bradley A. Williams and James W. Fleming Chemistry Division, Code 61x5 US Naval Research Lnhoratory Washington, DC 20375-5342, USA INTRODUCTION Alkali metal compounds, particularly those of sodium and potassium, are widely used as fire suppressants. Of particular note is that small NuHCOi particles have been found to be 2-4 times more effective by mass than Halon 1301 in extinguishing both eountertlow flames [ I] and cup- burner flames [?]. Furthermore, studies in our laboratory have found that potassium bicarbonate is some 2.5 times more efficient by weight at suppression than sodium bicarhonatc. The primary limitation associated with the use of alkali metal compounds is dispersal. since all known compounds have very low volatility and must he delivered to the fire either as powders or in (usually aqueous) solution. Although powders based on alkali metals have been used for many years, their mode of effective- ness has not generally been agreed upon. Thermal effects [3],namely, the vaporization of the particles as well as radiative energy transfer out of the flame. and both homogeneous (gas phase) and heterogeneous (surface) chemistry have been postulated as mechanisms by which alkali metals suppress fires [4]. Complicating these issues is the fact that for powders, particle size and morphology have been found to affect the suppression properties significantly [I]. In addition to sodium and potassium, other alkali metals have been studied, albeit to a consider- ably lesser extent. The general finding is that the suppression effectiveness increases with atomic weight: potassium is more effective than sodium, which is in turn more effective than lithium [4]. -
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. -
FRANCIUM Element Symbol: Fr Atomic Number: 87
FRANCIUM Element Symbol: Fr Atomic Number: 87 An initiative of IYC 2011 brought to you by the RACI KAYE GREEN www.raci.org.au FRANCIUM Element symbol: Fr Atomic number: 87 Francium (previously known as eka-cesium and actinium K) is a radioactive metal and the second rarest naturally occurring element after Astatine. It is the least stable of the first 103 elements. Very little is known of the physical and chemical properties of Francium compared to other elements. Francium was discovered by Marguerite Perey of the Curie Institute in Paris, France in 1939. However, the existence of an element of atomic number 87 was predicted in the 1870s by Dmitri Mendeleev, creator of the first version of the periodic table, who presumed it would have chemical and physical properties similar to Cesium. Several research teams attempted to isolate this missing element, and there were at least four false claims of discovery during which it was named Russium (after the home country of soviet chemist D. K. Dobroserdov), Alkalinium (by English chemists Gerald J. K. Druce and Frederick H. Loring as the heaviest alkali metal), Virginium (after Virginia, home state of chemist Fred Allison), and Moldavium (by Horia Hulubei and Yvette Cauchois after Moldavia, the Romanian province where they conducted their work). Perey finally discovered Francium after purifying radioactive Actinium-227 from Lanthanum, and detecting particles decaying at low energy levels not previously identified. The new product exhibited chemical properties of an alkali metal (such as co-precipitating with Cesium salts), which led Perey to believe that it was element 87, caused by the alpha radioactive decay of Actinium-227. -
BISMUTH LEAD ALLOY Synonyms BISMUTH ALLOY, 5805, HS CODE 78019900 ● NYRSTAR LEAD ALLOYS
1. IDENTIFICATION OF THE MATERIAL AND SUPPLIER 1.1 Product identifier Product name BISMUTH LEAD ALLOY Synonyms BISMUTH ALLOY, 5805, HS CODE 78019900 ● NYRSTAR LEAD ALLOYS 1.2 Uses and uses advised against Uses ALLOY Used for further refining of bismuth and lead metals. 1.3 Details of the supplier of the product Supplier name NYRSTAR PORT PIRIE Address PO Box 219, Port Pirie, SA, 5540, AUSTRALIA Telephone (08) 8638 1500 Fax (08) 8638 1583 Website http://www.nyrstar.com 1.4 Emergency telephone numbers Emergency (08) 8638 1500 2. HAZARDS IDENTIFICATION 2.1 Classification of the substance or mixture CLASSIFIED AS HAZARDOUS ACCORDING TO SAFE WORK AUSTRALIA CRITERIA GHS classifications Acute Toxicity: Oral: Category 4 Acute Toxicity: Inhalation: Category 4 Toxic to Reproduction: Category 1A Specific Target Organ Systemic Toxicity (Repeated Exposure): Category 2 2.2 GHS Label elements Signal word DANGER Pictograms Hazard statements H302 Harmful if swallowed. H332 Harmful if inhaled. H360 May damage fertility or the unborn child. H373 May cause damage to organs through prolonged or repeated exposure. Prevention statements P202 Do not handle until all safety precautions have been read and understood. P260 Do not breathe dust/fume/gas/mist/vapours/spray. P264 Wash thoroughly after handling. P270 Do not eat, drink or smoke when using this product. P271 Use only outdoors or in a well-ventilated area. P281 Use personal protective equipment as required. SDS Date: 08 Jun 2018 Page 1 of 7 Version No: 1.3 PRODUCT NAME BISMUTH LEAD ALLOY Response statements P304 + P340 IF INHALED: Remove to fresh air and keep at rest in a position comfortable for breathing. -
The Separation of Bismuth-213 from Actinium-225 and the Ion Exchange Properties of the Alkali Metal Cations with an Inorganic Resin
University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Doctoral Dissertations Graduate School 12-2017 The Separation of Bismuth-213 from Actinium-225 and the Ion Exchange Properties of the Alkali Metal Cations with an Inorganic Resin Mark Alan Moore University of Tennessee Follow this and additional works at: https://trace.tennessee.edu/utk_graddiss Recommended Citation Moore, Mark Alan, "The Separation of Bismuth-213 from Actinium-225 and the Ion Exchange Properties of the Alkali Metal Cations with an Inorganic Resin. " PhD diss., University of Tennessee, 2017. https://trace.tennessee.edu/utk_graddiss/4848 This Dissertation is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a dissertation written by Mark Alan Moore entitled "The Separation of Bismuth-213 from Actinium-225 and the Ion Exchange Properties of the Alkali Metal Cations with an Inorganic Resin." I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Doctor of Philosophy, with a major in Chemical Engineering. Robert Counce, Major Professor We have read this dissertation and recommend its acceptance: Paul Dalhaimer, Howard Hall, George Schweitzer, Jack Watson Accepted for the Council: Dixie L. Thompson Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) The Separation of Bismuth-213 from Actinium-225 and the Ion Exchange Properties of the Alkali Metal Cations with an Inorganic Resin A Dissertation Presented for the Doctor of Philosophy Degree The University of Tennessee, Knoxville Mark Alan Moore December 2017 Copyright © 2017 by Mark A.