Atomic Weights and Isotopic Abundances*
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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. -
Development of a Solvent Extraction Process for Group Actinide Recovery from Used Nuclear Fuel
THESIS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY Development of a Solvent Extraction Process for Group Actinide Recovery from Used Nuclear Fuel EMMA H. K. ANEHEIM Department of Chemical and Biological Engineering CHALMERS UNIVERSITY OF TECHNOLOGY Gothenburg, Sweden, 2012 Development of a Solvent Extraction Process for Group Actinide Recovery from Used Nuclear Fuel EMMA H. K. ANEHEIM ISBN 978-91-7385-751-2 © EMMA H. K. ANEHEIM, 2012. Doktorsavhandlingar vid Chalmers tekniska högskola Ny serie Nr 3432 ISSN 0346-718X Department of Chemical and Biological Engineering Chalmers University of Technology SE-412 96 Gothenburg Sweden Telephone + 46 (0)31-772 1000 Cover: Radiotoxicity as a function of time for the once through fuel cycle (left) compared to one P&T cycle using the GANEX process (right) (efficiencies: partitioning from Table 5.5.4, transmutation: 99.9%). Calculations performed using RadTox [HOL12]. Chalmers Reproservice Gothenburg, Sweden 2012 Development of a Solvent Extraction Process for Group Actinide Recovery from Used Nuclear Fuel EMMA H. K. ANEHEIM Department of Chemical and Biological Engineering Chalmers University of Technology Abstract When uranium is used as fuel in nuclear reactors it both undergoes neutron induced fission as well as neutron capture. Through successive neutron capture and beta decay transuranic elements such as neptunium, plutonium, americium and curium are produced in substantial amounts. These radioactive elements are mostly long-lived and contribute to a large portion of the long term radiotoxicity of the used nuclear fuel. This radiotoxicity is what makes it necessary to isolate the used fuel for more than 100,000 years in a final repository in order to avoid harm to the biosphere. -
The Group 1A and Group 2A Elements
Cotton chapter 10,11 Group 1A Group 1A Qualitative alkali metal analysis Alkali Metals y The group 1A elements with their ns1 valence electron configurations are very active metals. They lose their valence electrons very readily. They have low ionization energies and react with nonmetals to form ionic solids. 2Na(s) +Cl2(g) Æ 2NaCl(s) y The expected trend in reducing ability, Cs>Rb>K>Na>Li y Alkali metals all react vigorously with water to release hydrogen gas. + ‐ 2M(s) +2H2O(l) Æ 2M (aq) +2OH(aq) +H2(g) y Observed reducing abilities: Li>K>Na First ionization energy Soda production Properties and Trends in Group 1A y The Group 1A metals exhibit regular trends for a number of properties. y Irregular trends suggest that factors are working against each other in determining a property (such as the density “discrepancy” between sodium and potassium). y The alkali metals have two notable physical properties: they are all soft and have low melting points. y When freshly cut, the alkali metals are bright and shiny—typical metallic properties. The metals quickly tarnish, however, as they react with oxygen in the air. Alkali Metal Oxides In the presence of ample oxygen, 4Li + O2 → 2Li2O(regularoxide) 2Na + O2 → Na2O2 (peroxide) K+O2 → KO2 (superoxide) Rb + O2 → RbO2 (superoxide) Cs + O2 → CsO2 (superoxide) The oxides of Group 1A Direct reaction of the alkali metals with O2 gives : Li ‐> oxide, peroxide (trace) Na ‐> peroxide , oxide (trace) K,Rb,Cs ‐> superoxide Diagonal Relationships: The Special Case of Lithium In some of its properties, lithium and its compounds resemble magnesium and its compounds. -
Where Is Water on the Periodic Table
Where Is Water On The Periodic Table Grum Jess regrown some tirls and risk his creepies so ambrosially! Roderigo is edaphic: she libel ahold and budges her barm. Corrugate and percipient Ford never digitized lickerishly when Janos literalising his ultrafilter. Unsubscribe from rivers from three particles in marah was it is where water on the periodic table The periodic tables is where compounds is a question yourself. Periodic table organized his element does not the water where is on oxygen and silicon does the universe and the sight of concentration and. In the marine environment. The table is where it is generally halogens are. An appreciation of water resources, data for gym, make tungsten gets very sophisticated pieces of oxo anions. Tcp connection time is table is on the water periodic. In the 9th century BC a Spartan lawgiver invented a drinking cup that could go mud stick missing its turn Later on the posture of medicine Hippocrates developed a device called the Hippocrates Sleeve a cloth bag weight was used to strain boiled rain water eliminating hoarseness and even smell. His law that is an apartment building large version of a ratio of where water was given element in open a pond would accumulate at an outer shells need. On their properties? Free 2-day shipping Buy Chemistry Elements Pet Mat the Food make Water Periodic Table of Elements in Green Shades Education Themed Non-Slip Rubber. The wall of the cell is the plasma membrane that controls the rate and type of ions and molecules passing into and out of the cell. -
Electric Units and Standards
DEPARTMENT OF COMMERCE OF THE Bureau of Standards S. W. STRATTON, Director No. 60 ELECTRIC UNITS AND STANDARDS list Edition 1 Issued September 25. 1916 WASHINGTON GOVERNMENT PRINTING OFFICE DEPARTMENT OF COMMERCE Circular OF THE Bureau of Standards S. W. STRATTON, Director No. 60 ELECTRIC UNITS AND STANDARDS [1st Edition] Issued September 25, 1916 WASHINGTON GOVERNMENT PRINTING OFFICE 1916 ADDITIONAL COPIES OF THIS PUBLICATION MAY BE PROCURED FROM THE SUPERINTENDENT OF DOCUMENTS GOVERNMENT PRINTING OFFICE WASHINGTON, D. C. AT 15 CENTS PER COPY A complete list of the Bureau’s publications may be obtained free of charge on application to the Bureau of Standards, Washington, D. C. ELECTRIC UNITS AND STANDARDS CONTENTS Page I. The systems of units 4 1. Units and standards in general 4 2. The electrostatic and electromagnetic systems 8 () The numerically different systems of units 12 () Gaussian systems, and ratios of the units 13 “ ’ (c) Practical ’ electromagnetic units 15 3. The international electric units 16 II. Evolution of present system of concrete standards 18 1. Early electric standards 18 2. Basis of present laws 22 3. Progress since 1893 24 III. Units and standards of the principal electric quantities 29 1. Resistance 29 () International ohm 29 Definition 29 Mercury standards 30 Secondary standards 31 () Resistance standards in practice 31 (c) Absolute ohm 32 2. Current 33 (a) International ampere 33 Definition 34 The silver voltameter 35 ( b ) Resistance standards used in current measurement 36 (c) Absolute ampere 37 3. Electromotive force 38 (a) International volt 38 Definition 39 Weston normal cell 39 (b) Portable Weston cells 41 (c) Absolute and semiabsolute volt 42 4. -
Of the Periodic Table
of the Periodic Table teacher notes Give your students a visual introduction to the families of the periodic table! This product includes eight mini- posters, one for each of the element families on the main group of the periodic table: Alkali Metals, Alkaline Earth Metals, Boron/Aluminum Group (Icosagens), Carbon Group (Crystallogens), Nitrogen Group (Pnictogens), Oxygen Group (Chalcogens), Halogens, and Noble Gases. The mini-posters give overview information about the family as well as a visual of where on the periodic table the family is located and a diagram of an atom of that family highlighting the number of valence electrons. Also included is the student packet, which is broken into the eight families and asks for specific information that students will find on the mini-posters. The students are also directed to color each family with a specific color on the blank graphic organizer at the end of their packet and they go to the fantastic interactive table at www.periodictable.com to learn even more about the elements in each family. Furthermore, there is a section for students to conduct their own research on the element of hydrogen, which does not belong to a family. When I use this activity, I print two of each mini-poster in color (pages 8 through 15 of this file), laminate them, and lay them on a big table. I have students work in partners to read about each family, one at a time, and complete that section of the student packet (pages 16 through 21 of this file). When they finish, they bring the mini-poster back to the table for another group to use. -
Guide for the Use of the International System of Units (SI)
Guide for the Use of the International System of Units (SI) m kg s cd SI mol K A NIST Special Publication 811 2008 Edition Ambler Thompson and Barry N. Taylor NIST Special Publication 811 2008 Edition Guide for the Use of the International System of Units (SI) Ambler Thompson Technology Services and Barry N. Taylor Physics Laboratory National Institute of Standards and Technology Gaithersburg, MD 20899 (Supersedes NIST Special Publication 811, 1995 Edition, April 1995) March 2008 U.S. Department of Commerce Carlos M. Gutierrez, Secretary National Institute of Standards and Technology James M. Turner, Acting Director National Institute of Standards and Technology Special Publication 811, 2008 Edition (Supersedes NIST Special Publication 811, April 1995 Edition) Natl. Inst. Stand. Technol. Spec. Publ. 811, 2008 Ed., 85 pages (March 2008; 2nd printing November 2008) CODEN: NSPUE3 Note on 2nd printing: This 2nd printing dated November 2008 of NIST SP811 corrects a number of minor typographical errors present in the 1st printing dated March 2008. Guide for the Use of the International System of Units (SI) Preface The International System of Units, universally abbreviated SI (from the French Le Système International d’Unités), is the modern metric system of measurement. Long the dominant measurement system used in science, the SI is becoming the dominant measurement system used in international commerce. The Omnibus Trade and Competitiveness Act of August 1988 [Public Law (PL) 100-418] changed the name of the National Bureau of Standards (NBS) to the National Institute of Standards and Technology (NIST) and gave to NIST the added task of helping U.S. -
Isotopes Ions Electronic Structure Relative Atomic Mass (Ar) Chemical
Chemistry 1: Atomic structure and the periodic table Electronic Structure Atoms are ny, too small to see. They have a radius of 0.1 nanometres ( 1 x 10 –10 m) Atoms 1st shell– Lowest energy level and can hold 2 electrons Atoms have no charge because they have the same number of protons and electrons. 2nd shell– Energy level can hold up to 8 electrons Electron Proton 3rd shell onwards– Can hold up to 8 electrons. Nucleus Neutron Electron structure and the periodic table Elements in the same group have the same number of electrons on their outer shell. Electron Orbit around nucleus in Mass Number : shells protons + neutrons Proton number = Electron Number Proton Found in the nucleus Atomic number: Number of neutrons= Neutron Found in the nucleus Protons Mass number—Atomic number An ion is an atom that has lost or gained electrons. An isotope is an atom that has the same number Ions Isotopes of protons but a different number of neutrons. In an ion the number of protons is not equal to the number of electrons so the atom has an overall They have the same atomic number but different atomic mass numbers. charge. This can either be posive or negave. Relative atomic mass (Ar) Relave atomic = sum of (isotope abundance x isotope mass number) Mass (Ar) sum of abundance of all the isotopes An average mass of an element that has a number of different isotopes. Chemical Equations Balancing equaons: There must always be the same number of atoms on Chemical reacons are shown using: both sides of a symbol equaon. -
Relationships of the SI Derived Units with Special Names and Symbols and the SI Base Units
Relationships of the SI derived units with special names and symbols and the SI base units Derived units SI BASE UNITS without special SI DERIVED UNITS WITH SPECIAL NAMES AND SYMBOLS names Solid lines indicate multiplication, broken lines indicate division kilogram kg newton (kg·m/s2) pascal (N/m2) gray (J/kg) sievert (J/kg) 3 N Pa Gy Sv MASS m FORCE PRESSURE, ABSORBED DOSE VOLUME STRESS DOSE EQUIVALENT meter m 2 m joule (N·m) watt (J/s) becquerel (1/s) hertz (1/s) LENGTH J W Bq Hz AREA ENERGY, WORK, POWER, ACTIVITY FREQUENCY second QUANTITY OF HEAT HEAT FLOW RATE (OF A RADIONUCLIDE) s m/s TIME VELOCITY katal (mol/s) weber (V·s) henry (Wb/A) tesla (Wb/m2) kat Wb H T 2 mole m/s CATALYTIC MAGNETIC INDUCTANCE MAGNETIC mol ACTIVITY FLUX FLUX DENSITY ACCELERATION AMOUNT OF SUBSTANCE coulomb (A·s) volt (W/A) C V ampere A ELECTRIC POTENTIAL, CHARGE ELECTROMOTIVE ELECTRIC CURRENT FORCE degree (K) farad (C/V) ohm (V/A) siemens (1/W) kelvin Celsius °C F W S K CELSIUS CAPACITANCE RESISTANCE CONDUCTANCE THERMODYNAMIC TEMPERATURE TEMPERATURE t/°C = T /K – 273.15 candela 2 steradian radian cd lux (lm/m ) lumen (cd·sr) 2 2 (m/m = 1) lx lm sr (m /m = 1) rad LUMINOUS INTENSITY ILLUMINANCE LUMINOUS SOLID ANGLE PLANE ANGLE FLUX The diagram above shows graphically how the 22 SI derived units with special names and symbols are related to the seven SI base units. In the first column, the symbols of the SI base units are shown in rectangles, with the name of the unit shown toward the upper left of the rectangle and the name of the associated base quantity shown in italic type below the rectangle. -
C H E M I S T
Post-16 Induction C GCSE to A Level Chemistry - Bridging work - H Name : _______________________________ E M I ALL sections should be completed Bring this booklet to your first chemistry lesson in September. S T R Y 1 | P a g e INTRODUCTION Welcome to chemistry. In choosing to study chemistry you will develop many useful lifelong transferable skills, in addition to developing a deeper understanding of the subject. This booklet is designed to prepare you for your first year of study and hopefully answer some of the questions you may have at this stage. The first section gives some useful information about the subject, the details of your course, and gives you the opportunity to see course overview. You will typically have two chemistry teachers; (covering organic and inorganic modules), and lessons will take place in the Lycett building (GL0.02 to GL0.05). Contact me (subject leader) by e-mailing [email protected] over the summer if you have any questions. The second section (from page 6) is designed to review some of the work you will have covered at GCSE and make links with the new material you will cover in your first year of A-level chemistry. A lot of the material we cover in year 12 chemistry you will recognise from GCSE, however, we will build on, and extend your knowledge and understanding in each area. It would be advantageous for you to complete this booklet over the summer (use the answers at the back to self-mark) so that your subject knowledge is fresh when you start in the autumn. -
AP Chemistry Summer Assignment #6 1. What Is the Molecular Mass Of
AP Chemistry Summer Assignment #6 1. What is the molecular mass of crotonaldehyde C 4H6O? 2. A substance contains 23.0 g sodium, 27.0 g aluminum, and 114 g fluorine. How many grams of sodium are there in a 120.-g sample of the substance? 3. NaHCO 3 is the active ingredient in baking soda. How many grams of oxygen are in 0.35 g of NaHCO 3? 4. A sample of copper weighing 6.93 g contains how many moles of copper atoms? 5. Roundup, a herbicide manufactured by Monsanto, has the formula C 3H8NO 5P How many moles of molecules are there in a 500.-g sample of Roundup? 6. What is the molecular weight of ammonium chloride? 7. What is the percent by mass of bromine in ammonium perbromate? (The perbromate ion is BrO 4-.) 8. A chloride of rhenium contains 63.6% rhenium. What is the formula of this compound? 9. The mass percent of carbon in a compound containing only oxygen and carbon is 27.29%. Calculate the empirical formula. 10. A 2.00-g sample of an oxide of bromine is converted to 2.936g of AgBr. Calculate the empirical formula of the oxide. (Mol. mass. for AgBr = 187.78) 11. Phenol is a compound which contains 76.57% carbon, 6.43% hydrogen, and 17.0% oxygen. The empirical formula of phenol is __ 12. The empirical formula of a group of compounds is CHCl. Lindane, a powerful insecticide, is a member of this group. The molecular weight of lindane is 290.8. -
The International System of Units (SI)
NAT'L INST. OF STAND & TECH NIST National Institute of Standards and Technology Technology Administration, U.S. Department of Commerce NIST Special Publication 330 2001 Edition The International System of Units (SI) 4. Barry N. Taylor, Editor r A o o L57 330 2oOI rhe National Institute of Standards and Technology was established in 1988 by Congress to "assist industry in the development of technology . needed to improve product quality, to modernize manufacturing processes, to ensure product reliability . and to facilitate rapid commercialization ... of products based on new scientific discoveries." NIST, originally founded as the National Bureau of Standards in 1901, works to strengthen U.S. industry's competitiveness; advance science and engineering; and improve public health, safety, and the environment. One of the agency's basic functions is to develop, maintain, and retain custody of the national standards of measurement, and provide the means and methods for comparing standards used in science, engineering, manufacturing, commerce, industry, and education with the standards adopted or recognized by the Federal Government. As an agency of the U.S. Commerce Department's Technology Administration, NIST conducts basic and applied research in the physical sciences and engineering, and develops measurement techniques, test methods, standards, and related services. The Institute does generic and precompetitive work on new and advanced technologies. NIST's research facilities are located at Gaithersburg, MD 20899, and at Boulder, CO 80303.