Transition Elements Periodic Table
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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". -
Why Do Transition Metals Have Similar Properties
Why Do Transition Metals Have Similar Properties Saturnalian Haydon never reek so round-the-clock or spruik any explanations in-flight. Cerebrovascular Elisha parries his weasands delaminating disproportionably. Dan divulgate her ohm ought, randy and grouchy. Based on the coinage metals do have low electronegativity The similar properties do transition have similar. However, the trends in these values show the usual discontinuity half way along the series. This chapter on contact, why do transition have similar properties, why does it has both of! What is the major use today cadmium also extend across the oxidizing agent in the row of exceptions to accept varying numbers exhibit so that have similar. Oh, sorry I apologize on that. The more highly charged the ion, the more electrons you have to remove and the more ionisation energy you will have to provide. Transition metals in everything from hand is more rapidly when you would you typically, why do transition have similar properties identified in ionisation energy as inner electrons can be reduced, including superconducting magnets. Here is a result, why transition metals are heated, as is still others, can ask that attack dcp molecules. Density and malleable, why do transition metals have similar properties because cobalt atom of energy for you can be determined by consuming concentrated sulfuric acid with pyrolusite. Make sure to remember your password. It has the symbol Rh. We expect to the new york: he devised the needs no difference between two electrons go now what do transition have similar properties. Also, we do not collect or ask for personally identifiable information on any of our sites. -
A New Occurrence of Terrestrial Native Iron in the Earth's Surface
geosciences Article A New Occurrence of Terrestrial Native Iron in the Earth’s Surface: The Ilia Thermogenic Travertine Case, Northwestern Euboea, Greece Christos Kanellopoulos 1,2,* ID , Eugenia Valsami-Jones 3,4, Panagiotis Voudouris 1, Christina Stouraiti 1 ID , Robert Moritz 2, Constantinos Mavrogonatos 1 ID and Panagiotis Mitropoulos 1,† 1 Department of Geology and Geoenvironment, National and Kapodistrian University of Athens, Panepistimioupolis Zografou, 15784 Athens, Greece; [email protected] (P.V.); [email protected] (C.S.); [email protected] (C.M.); [email protected] (P.M.) 2 Section of Earth and Environmental Sciences, University of Geneva, Rue des Maraichers 13, 1205 Geneva, Switzerland; [email protected] 3 School of Geography, Earth & Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; [email protected] 4 Department of Earth Sciences, Natural History Museum London, Cromwell Road, London SW7 5BD, UK * Correspondence: [email protected] † Professor Panagiotis Mitropoulos has passed away in 2017. Received: 6 April 2018; Accepted: 23 July 2018; Published: 31 July 2018 Abstract: Native iron has been identified in an active thermogenic travertine deposit, located at Ilia area (Euboea Island, Greece). The deposit is forming around a hot spring, which is part of a large active metallogenetic hydrothermal system depositing ore-bearing travertines. The native iron occurs in two shapes: nodules with diameter 0.4 and 0.45 cm, and angular grains with length up to tens of µm. The travertine laminae around the spherical/ovoid nodules grow smoothly, and the angular grains are trapped inside the pores of the travertine. -
Synthesis and Characterization of the New Uranium Yttrium Oxysulfide
ARTICLE IN PRESS Journal of Solid State Chemistry 182 (2009) 1861–1866 Contents lists available at ScienceDirect Journal of Solid State Chemistry journal homepage: www.elsevier.com/locate/jssc Synthesis and characterization of the new uranium yttrium oxysulfide UY4O3S5 Geng Bang Jin a, Eun Sang Choi b, Daniel M. Wells a, James A. Ibers a,Ã a Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3113, USA b Department of Physics and National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA article info abstract Article history: Red needles of UY4O3S5 have been synthesized by the solid-state reaction at 1273 K of UOS and Y2S3 Received 16 January 2009 with Sb2S3 as a flux. UY4O3S5 adopts a three-dimensional structure that contains five crystal- Received in revised form lographically unique heavy-atom positions. U and Y atoms disorder on one eight-coordinate metal 11 April 2009 position bonded to four O atoms and four S atoms and two seven-coordinate metal positions bonded to Accepted 20 April 2009 three O atoms and four S atoms. Another eight-coordinate metal position with two O and six S atoms Available online 3 May 2009 and one six-coordinate metal position with six S atoms are exclusively occupied by Y atoms. UY4O3S5 is Keywords: a modified Curie–Weiss paramagnet between 1.8 and 300 K. Its effective magnetic moment is estimated Uranium yttrium oxysulfide to be 3.3(2) mB.UY4O3S5 has a band gap of 1.95 eV. The electrical resistivity along the [010] direction of a X-ray crystal structure single crystal shows Arrhenius-type thermal activation with an activation energy of 0.2 eV. -
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 -
Stability of Coinage Metals Interacting with C60
nanomaterials Article Stability of Coinage Metals Interacting with C60 Navaratnarajah Kuganathan 1,2,* , Ratnasothy Srikaran 3 and Alexander Chroneos 1,2 1 Department of Materials, Imperial College London, London SW7 2AZ, UK; [email protected] 2 Faculty of Engineering, Environment and Computing, Coventry University, Priory Street, Coventry CV1 5FB, UK; [email protected] 3 Department of Chemistry, University of Jaffna, Sir. Pon Ramanathan Road, Thirunelvely, Jaffna 40000, Srilanka; [email protected] * Correspondence: [email protected] or [email protected] Received: 27 September 2019; Accepted: 17 October 2019; Published: 18 October 2019 Abstract: Buckminsterfullerene (C60) has been advocated as a perfect candidate material for the encapsulation and adsorption of a variety of metals and the resultant metallofullerenes have been considered for the use in different scientific, technological and medical areas. Using spin-polarized density functional theory together with dispersion correction, we examine the stability and electronic structures of endohedral and exohedral complexes formed between coinage metals (Cu, Ag and Au) and both non-defective and defective C60. Encapsulation is exoergic in both forms of C60 and their encapsulation energies are almost the same. Exohedral adsorption of all three metals is stronger than that of endohedral encapsulation in the non-defective C60. Structures and the stability of atoms interacting with an outer surface of a defective C60 are also discussed. As the atoms are stable both inside and outside the C60, the resultant complexes can be of interest in different scientific and medical fields. Furthermore, all complexes exhibit magnetic moments, inferring that they can be used as spintronic materials. -
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. -
Atomic Weights of the Elements 1995
Atomic Weights of the Elements 1995 Cite as: Journal of Physical and Chemical Reference Data 26, 1239 (1997); https:// doi.org/10.1063/1.556001 Submitted: 02 May 1997 . Published Online: 15 October 2009 T. B. Coplen ARTICLES YOU MAY BE INTERESTED IN Atomic Weights of the Elements 1999 Journal of Physical and Chemical Reference Data 30, 701 (2001); https:// doi.org/10.1063/1.1395055 Journal of Physical and Chemical Reference Data 26, 1239 (1997); https://doi.org/10.1063/1.556001 26, 1239 © 1997 American Institute of Physics and American Chemical Society. Atomic Weights of the Elements 1995a) T. B. Coplen U. S. Geological Survey, Reston, Virginia 20192 Received May 2, 1997; revised manuscript received June 13, 1997 The biennial review of atomic weight, Ar~E!, determinations and other cognate data has resulted in changes for the standard atomic weight of 21 elements. The five most significant changes are: boron from 10.81160.005 to 10.81160.007; carbon from 12.01160.001 to 12.010760.0008; arsenic from 74.9215960.00002 to 74.9216060.00002; cerium from 140.11560.004 to 140.11660.001; and platinum 195.0860.03 to 195.07860.002. An annotation for potassium has been changed in the Table of Standard Atomic Weights. To eliminate possible confusion in the reporting of relative lithium isotope-ratio data, the Commission recommends that such data be ex- pressed using 7Li/6Li ratios and that reporting using 6Li/7Li ratios be discontinued. Be- cause relative isotope-ratio data for sulfur are commonly being expressed on noncorre- sponding scales, the Commission recommends that such isotopic data be expressed relative to VCDT ~Vienna Can˜on Diablo Troilite! on a scale such that 34S/32S of IAEA- S-1 silver sulfide is 0.9997 times that of VCDT. -
Stoichiometry: the Reaction of Iron with Copper(II) Sulfate
CEAC 103 GENERAL CHEMISTRY Experiment 2 Stoichiometry: The Reaction of Iron with Copper(II) Sulfate Purpose: To enhance the understanding of stoichiometry, a reaction between iron and copper (II) sulfate solution will be conducted. This will help you to differentiate limiting and excess reactant in a chemical reaction. Finally the theoretical and percent yield of this reaction will be calculated. Theory Stoichiometry is the measurement of quantitative relationships in chemical formulas and equations. In this experiment stoichiometric principles will be used to obtain the appropriate equation between the reaction of iron metal and copper(II) sulfate solution. After the reaction is taking place, the formation of metallic copper, which is seen precipitating as a finely divided reddish-orange powder will be observed. This reaction is one of the example of single substitution reaction in which one element “displaces” from a compound by another element. The element which has ability of displacing other element from compound is said to be “more active” than the displaced metal. In this experiment, iron is more active than copper. Two distinct forms of iron are present, namely Fe2+ and Fe3+. Stoichiometric principles will be used to determine which reaction is more dominant compared to other one by examining the reaction between iron and copper (II) sulfate solution. If Fe2+ is formed, then equation (1) is dominant, while equation (2) will be selected if Fe3+ is formed. This can be determined 1 according to mole ratio of copper to iron. If the moles of copper is equal to the moles of iron, then equation (1) has taken place. -
Chromium Compounds Hazard Summary
Chromium Compounds Hazard Summary Chromium occurs in the environment primarily in two valence states, trivalent chromium (Cr III) and hexavalent chromium (Cr VI). Exposure may occur from natural or industrial sources of chromium. Chromium III is much less toxic than chromium (VI). The respiratory tract is also the major target organ for chromium (III) toxicity, similar to chromium (VI). Chromium (III) is an essential element in humans. The body can detoxify some amount of chromium (VI) to chromium (III). The respiratory tract is the major target organ for chromium (VI) toxicity, for acute (short-term) and chronic (long-term) inhalation exposures. Shortness of breath, coughing, and wheezing were reported from a case of acute exposure to chromium (VI), while perforations and ulcerations of the septum, bronchitis, decreased pulmonary function, pneumonia, and other respiratory effects have been noted from chronic exposure. Human studies have clearly established that inhaled chromium (VI) is a human carcinogen, resulting in an increased risk of lung cancer. Animal studies have shown chromium (VI) to cause lung tumors via inhalation exposure. Please Note: The main sources of information for this fact sheet are EPA's Integrated Risk Information System (IRIS) (7), which contains information on inhalation chronic toxicity and the RfC and oral chronic toxicity and the RfD, and the carcinogenic effects of chromium including the unit cancer risk for inhalation exposure, EPA's Toxicological Review of Trivalent Chromium and Toxicological Review of Hexavalent Chromium (3), and the Agency for Toxic Substances and Disease Registry's (ATSDR's) Toxicological Profile for Chromium. (1) Uses The metal chromium is used mainly for making steel and other alloys. -
Electronic Structure of Ytterbium(III) Solvates – a Combined Spectro
Electronic Structure of Ytterbium( III) Solvates – A Combined Spectro- scopic and Theoretical Study Nicolaj Kofod,† Patrick Nawrocki,† Carlos Platas-Iglesias,*,‡ Thomas Just Sørensen*,† † Department of Chemistry and Nano-Science Center, University of Copenhagen, Universitetsparken 5, 2100 København Ø, Den- mark. ‡ Centro de Investigacións Científicas Avanzadas and Departamento de Química, Universidade da Coruña, Campus da Zapateira-Rúa da Fraga 10, 15008 A Coruña, Spain ABSTRACT: The wide range of optical and magnetic properties of the lanthanide(III) ions is associated to their intricate electronic structures, which in contrast to lighter elements is characterized by strong relativistic effects and spin-orbit coupling. Nevertheless, computational methods are now capable of describing the ladder of electronic energy levels of the simpler trivalent lanthanide ions, as well as the lowest energy term of most of the series. The electronic energy levels result from electron configurations that are first split by spin-orbit coupling into groups of energy levels denoted by the corresponding Russel-Saunders terms. Each of these groups are then split by the ligand field into the actual electronic energy levels known as microstates or sometimes mJ levels. The ligand field splitting directly informs on coordination geometry, and is a valuable tool for determining structure and thus correlating the structure and properties of metal complexes in solution. The issue with lanthanide com- plexes is that the determination of complex structures from ligand field splitting remains a very challenging task. In this manuscript, the optical spectra – absorption, luminescence excitation and luminescence emission – of ytterbium(III) solvates were recorded in water, methanol, dime- thyl sulfoxide and N,N-dimethylformamide. -
Why Isn't Hafnium a Noble Gas? Also More on the Lanthanide Contraction
return to updates Period 6 Why Isn't Hafnium a Noble Gas? also more on the Lanthanide contraction by Miles Mathis First published March 30, 2014 This paper replaces my earlier paper on the Lanthanides After a long break, it is time I returned to the Periodic Table. Many readers probably wish I would concentrate more on one subject, or at least one area of physics or chemistry. Possibly, they think I would get more done that way. They are mistaken. I would indeed get more done in that one field, and if that is their field, of course that would satisfy them more personally. But by skipping around, I actually maximize my production. How? One, I stay fresh. I don't get bored by staying in one place too long, so my creativity stays at a peak. Two, I cross-pollinate my ideas. My readers have seen how often a discovery in one sub-field helps me in another sub-field, even when those two fields aren't adjacent. All of science (and life) is ultimately of a piece, so anything I learn anywhere will help me everywhere else. Three, being interested in a wide array of topics gives me a bigger net, and with a bigger net I am better able to capture solutions across the board. Knowledge isn't just a matter of depth, it is a matter of breadth. In philosophy classes, we were taught this as part of the hermeneutic circle: the parts feed the whole and the whole feeds back into all the parts.