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Chemistry: the Molecular Nature of Matter and Change
REVISED CONFIRMING PAGES The Components of Matter 2.1 Elements, Compounds, and 2.5 The Atomic Theory Today 2.8 Formula, Name, and Mass of Mixtures: An Atomic Overview Structure of the Atom a Compound 2.2 The Observations That Led to Atomic Number, Mass Number, and Binary Ionic Compounds an Atomic View of Matter Atomic Symbol Compounds That Contain Polyatomic Mass Conservation Isotopes Ions Definite Composition Atomic Masses of the Elements Acid Names from Anion Names Multiple Proportions 2.6 Elements: A First Look at the Binary Covalent Compounds The Simplest Organic Compounds: Dalton’s Atomic Theory Periodic Table 2.3 Straight-Chain Alkanes Postulates of the Atomic Theory Organization of the Periodic Table Masses from a Chemical Formula How the Atomic Theory Explains Classifying the Elements Representing Molecules with a the Mass Laws Compounds: An Introduction 2.7 Formula and a Model to Bonding 2.4 The Observations That Led to Mixtures: Classification and the Nuclear Atom Model The Formation of Ionic Compounds 2.9 Separation Discovery of the Electron and The Formation of Covalent An Overview of the Components of Its Properties Compounds Matter Discovery of the Atomic Nucleus (a) (b) (right) ©Rudy Umans/Shutterstock IN THIS CHAPTER . We examine the properties and composition of matter on the macroscopic and atomic scales. By the end of this chapter, you should be able to • Relate the three types of matter—elements or elementary substances, compounds, and mixtures—to the simple chemical entities that they comprise—atoms, ions, and molecules; -
Integrated M.Sc. Chemistry (CBCS) SYLLABUS Department of Chemistry Central University of Tamil Nadu Thiruvarur 610
Integrated M.Sc. Chemistry (CBCS) SYLLABUS Department of Chemistry Central University of Tamil Nadu Thiruvarur 610 101 Name of the course : Integrated M. Sc. (Chemistry) Duration : 10 semesters Intake : 30 Eligibility : Plus two examination or equivalent of any recognized board in India with 60% marks (Chemistry, Mathematics, Physics and Computer Science/Biology) for general category, 55% marks for OBC (Non-creamy layer) and 50% marks for SC/ST candidates. The candidates should not have completed 20 years of age as on 01-07-2015. Course Structure The five year program is spread into ten semesters where in first four semesters are designed for broad subject based understanding. Later six semesters will have increased focus on chemistry. The subject courses in the early stage of iM.Sc programme are simplified and of basic level that bolsters the inter-disciplinary way of learning. The third and subsequent year courses have been designed on advanced theories in chemistry with emphasis on concurrent modern laboratory techniques. Further the iM.Sc (Chemistry) programme has been included with experiments that provide exhaustive hands on experience on various sophisticated instruments, experimental techniques to enable the students secure jobs in corporate. The final semester is dedicated to specialization within the subject with research level training. The rules and regulations of Choice Based Credit System (CBCS) are applicable to this program. Generally, a student takes ten semesters to complete the program. The courses offered under CBCS, has certain credit number (2, 3 or 4). Core requirements of the programs are clearly defined. In the first two years of the program, a student has common course load with students from other departments. -
Project Note Weston Solutions, Inc
PROJECT NOTE WESTON SOLUTIONS, INC. To: Canadian Radium & Uranium Corp. Site File Date: June 5, 2014 W.O. No.: 20405.012.013.2222.00 From: Denise Breen, Weston Solutions, Inc. Subject: Determination of Significant Lead Concentrations in Sediment Samples References 1. New York State Department of Environmental Conservation. Technical Guidance for Screening Contaminated Sediments. March 1998. [45 pages] 2. U.S. Environmental Protection Agency (EPA) Office of Emergency Response. Establishing an Observed Release – Quick Reference Fact Sheet. Federal Register, Volume 55, No. 241. September 1995. [7 pages] 3. International Union of Pure and Applied Chemistry, Inorganic Chemistry Division Commission on Atomic Weights and Isotopic Abundances. Atomic Weights of Elements: Review 2000. 2003. [120 pages] WESTON personnel collected six sediment samples (including one environmental duplicate sample) from five locations along the surface water pathway of the Canadian Radium & Uranium Corp. (CRU) site in May 2014. The sediment samples were analyzed for Target Analyte List (TAL) Metals and Stable Lead Isotopes. 1. TAL Lead Interpretation: In order to quantify the significance for Lead, Thallium and Mercury the following was performed: 1. WESTON personnel tabulated all available TAL Metal data from the May 2014 Sediment Sampling event. 2. For each analyte of concern (Lead, Thallium, and Mercury), the highest background concentration was selected and then multiplied by three. This is the criteria to find the significance of site attributable release as per Hazard Ranking System guidelines. 3. One analytical lead result (2222-SD04) of 520 mg/kg (J) was qualified with an unknown bias. In accordance with US EPA document “Using Data to Document an Observed Release and Observed Contamination”, 2222-SD03 lead concentration was adjusted by dividing by the factor value for lead of 1.44 to equal 361 mg/kg. -
ISOTOPIC ELEMENTS) and the WHOLE NUMBER RULE for ATOMIC WEIGHTS by William D
624 CHEMISTRY: W. D. HARKINS PROC. N. A. -S. -To summarize, the mechanism tentatively proposed above may be dia.. grammatically represented as follows: Insulin Glycogen-*Hexose ---Hexose mono-phosphate Hexose di-phosphate-<r-Triose phosphate and Reactive triose Carbon Lactic dioxide acid and Water 1 It has recently been noted from the Zentralblatt that Euler and Myrback (Svensk. Kem. Tidskr., 36, 295-306 (1924)) have made an apparently similar suggestion. As the originAl article has not been available it has been impossible to learn how closely the two theories coincide. 2R. Robison, Biochem. J., 16, 809 (1922). 'This step has been definitely established by Harden and his co-workers and the enzyme accomplishing the change has been named hexosephosphatase. 4 Neuberg and Kerb, Biocerm. Zs., 58, 158-170. (1913). ' Euler and Myrback, Chemie Zele Gewebe, 12, 57 (1925). THE SEPARATION OF CHLORINE INTO ISOTOPES (ISOTOPIC ELEMENTS) AND THE WHOLE NUMBER RULE FOR ATOMIC WEIGHTS By WILLiAM D. HARKINs KENT CHEMICAL LABORATORY, UNIvRSITY OP CHCAGO Comminicated August 26, 1925 Introduction.-The existence of isotopes among the heaviest or radio- active elements was demonstrated by the difference in the rays emitted by "different radioactive elements of almost identical chemical properties" now designated as isotopes of the same chemical element. Isotopes have been shown to exist in the light elements by two independent methods: by their detection in the positive ray method, and by the actual separation of the isotopes. The earliest use of the positive ray method for detecting isotopes by J. J. Thomson' resulted in the discovery of the isotopes of neon, while the separation of chlorine into isotopic fractions by Harkins and Downloaded by guest on September 25, 2021 VOL. -
DOCUMENT RESUME ED 071 911 SE 015 548 TITLE Project Physics
DOCUMENT RESUME ED 071 911 SE 015 548 TITLE Project Physics Teacher Guide 6, The Nucleus. INSTITUTION Harvard Univ., Cambridge, Mass. Harvard Project Physics. SPONS AGENCY Office of Education (DHEW) Washington, D.C. Bureau of Research. BUREAU NO BR-5-1038 PUB DATE 68 CONTRACT OEC-5-10-058 NOTE 235p.; Authorized Interim Version EDRS PRICE MF-$0.65 HC-S9.87 DESCRIPTORS Instructional Materials; *Multimedia Instruction; *Nuclear Physics; Physics; *Radiation; Science Activities; Secondary Grades; *Secondary School Science; *Teaching Glides; Teaching Procedures IDENTIFIERS Harvard Project Physics ABSTRACT Teaching procedures of Project Physics Unit 6are presented to help teachers make effectiveuse of learning materials. Unit contents are discussed in connection withteaching aid lists, multi-media schedules, schedule blocks, andresource charts. Brief summaries are made for transparencies, 16mm films, and reader articles. Included is information about the backgroundand development of each unit chapter, procedures in demonstrations, apparatus operations, notes on the student handbook, andan explanation of film loops. Additional articlesare concerned with objects dated by radiocarbon, radiation safety, propertiesof radiations, radioactive sources, radioactivity determinationby electroscopes, and radiation detecting devices.Scalers, counters, Geiger tubes, and cadmium selenide photocellsare analyzed; and a bibliography of references is given, Solutionsto the study guide are provided in detail, and answers to test itemsare suggested. The sixth unit of the text, with marginal commentson each section, is also compiled in the manual. The work of Harvard ProjectPhysics has . been financially supported by: the Carnegie Corporation ofNew York, the Ford Foundation, the National Science Foundation,the Alfred P. Sloan Foundation, the United States office of Education,and Harvard University. -
Advanced Chemistry 1
ADVANCED CHEMISTRY 1 Philip Matthews B&& CAMBRIDGE UNIVERSITY PRESS Contents Acknowledgements pagex 5 Radioactive decay 28 How to use this book xi 5.1 Detection of radiation 28 5.2 Half-lives 29 5.3 The radioactive decay law 31 5.4 Decay schemes 31 PHYSICAL CHEMISTRY 6 Nuclear energy 34 1 Elements, atoms and electrons: basic 6.1 Discovery of nuclear energy 34 ideas 3 6.2 Fission reactions 34 1.1 Dalton's atomic theory 3 6.3 Nuclear power 35 1.2 Evidence for atoms 5 6.4 Fusion reactions 37 1.3 Cathode rays 6 6.5 Nuclear weapons 38 1.4 Millikan's experiment 6 1.5 Electric Charge is quantised 7 7 Applications of radioactivity 41 7.1 Industrial uses of radioactivity 41 2 Energy levels 9 7.2 Medical uses of radioactivity 42 2.1 Energy changes 9 7.3 Radiocarbon dating 42 2.2 Energy levels 9 7.4 Chemical applications 43 2.3 Max Planck and energy levels 11 2.4 Light energy 11 8 Bohr's model of the atom 46 8.1 Energy levels of the hydrogen atom 46 3 Atoms and the nucleus 13 8.2 How to calculate the ionisation energy of 3.1 A plum pudding 13 hydrogen 47 3.2 How the nucleus was discovered 13 8.3 What are Orbitals? 48 3.3 The discovery of protons 14 8.4 What are stationary states? 48 3.4 Moseley and atomic number 15 8.5 Ground and excited states 49 3.5 Discovery of neutrons 15 3.6 A comparison of electrons, protons and 9 The hydrogen atom spectrum 51 neutrons 16 9.1 Balmer's formula for the hydrogen atom 51 3.7 Isotopes 17 9.2 Bohr's explanation 51 3.8 Atomic mass units 17 9.3 Other lines in the hydrogen spectrum 51 3.9 Relative atomic and molecular -
Francis W. Aston
FRANCIS W. A STON Mass spectra and isotopes Nobel Lecture, December 12, 1922 Dalton’s statement of the Atomic Theory, which has been of such incalcu- lable value in the development of chemistry, contained the postulate that "atoms of the same element are similar to one another, and equal in weight". The second part of this postulate cannot, in general, be tested by chemical methods, for numerical ratios are only to be obtained in such methods by the use of quantities of the element containing countless myriads of atoms. At the same time it is somewhat surprising, when we consider the complete absence of positive evidence in its support, that no theoretical doubts were publicly expressed until late in the nineteenth century. There are two methods by which the postulate can be tested experi- mentally, either by comparing the weights of the individual atoms, or al- ternatively by demonstrating that samples of an element can exist which though chemically identical yet have different atomic weights. The latter method, by which the existence of isotopes was first proved, has been fully dealt with in the previous lecture by Professor Soddy. The more direct method, with which this lecture is concerned, can be applied by means of the analysis of positive rays. The condition for the development of these rays is briefly ionization at low pressure in a strong electric field. Ionization, which may be due to col- lisions or radiation, means in its simplest case the detachment of one electron from a neutral atom. The two resulting fragments carry charges of electricity of equal quantity but of opposite sign. -
Project Physics Text 6, the Nucleus. INSTITUTION Harvard Univ., Cambridge, Mass
DOCUMENT RESUME ED 071 910 SE 015 547 TITLE Project Physics Text 6, The Nucleus. INSTITUTION Harvard Univ., Cambridge, Mass. Harvard Protect Physics. SPONS AGENCY Office of Education (DHEW), Washington, D.C. Bureau of Research. BUREAU NO BR-5-1038 .PUB DATE 68 CONTRACT OEC-5-1C-058 NOTE 128p.; Authorized Interim Version EDRS PRICE brio-$0.65 HC -$6.58 DESCRIPTORS Instructional Materials; *Nuclear Physics; Physics; *Radiation; Radiation Effects; Radioisotopes; *Scientific Concepts; Secondary Grades; *Secondary School Science; *Textbooks IDENTIFIERS Harvard Project Physics ABSTRACT Nuclear physics fundamentals are presented in this sixth unit of the Project Physics text for use by senior high students. Included are discussions of radioactivity, taking into account Bacquerells discovery, radioactive elements, properties of radiations, radioactive transformations, decay series, and half-lives. Isotopes are analyzed in connection with positiverays, mass spectrographs, notations for nuclides and nuclear reactions, relative abundances, and atomic masses. Nuclear structures and reactions are studied by using proton-electron and proton-neutron hypotheses with a background of discoveries of neutrons, neutrinosas well as artificial transmutation and artificially induced radioactivity. Information about binding energy,mass-energy balance, nuclear fission and fusion, stellar nuclear reactions, nuclear force and model, and biological and medical application of radioisotopes is, given to conclude the whole text. Historical developmentsare stressed in -
William Draper Harkins
NATIONAL ACADEMY OF SCIENCES WILLIAM DRAPER H ARKINS 1873—1951 A Biographical Memoir by RO B E R T S . M ULLIKEN Any opinions expressed in this memoir are those of the author(s) and do not necessarily reflect the views of the National Academy of Sciences. Biographical Memoir COPYRIGHT 1975 NATIONAL ACADEMY OF SCIENCES WASHINGTON D.C. WILLIAM DRAPER HARKINS December 28, 1873-March 7', 1951 BY ROBERT S. MULLIKEN ILLIAM DRAPER HARKINS was a remarkable man. Although W he was rather late in beginning his career as professor of physical chemistry, his success was outstanding. He was a leader in nuclear physics at a time when American physicists were paying no attention to nuclei. Besides this, his work in chem- istry covers a broad range of physical chemistry, with especial emphasis on surface phenomena. He was a meticulous and re- sourceful experimenter, as well as an enterprising one, who did not hesitate to enter new fields and use new techniques. He participated broadly, not only in the development of pure science but also in its industrial applications. Harkins was born December 28, 1873, the son of Nelson Goodrich Harkins and Sarah Eliza (Draper) Harkins, in Titus- ville, Pennsylvania, then the heart of the new, booming oil industry. At the age of seven, he invested his entire capital of $12 in an oil well that his father had drilled in the Bradford, Pennsylvania, fields. This investment returned his capital several times. Fortunately for science, the returns were not great enough to attract him permanently into oil production. In 1892, at the age of nineteen, Harkins went to Escondido, California, near San Diego, to study Greek at the Escondido Seminary, a branch of the University of Southern California. -
Development of Mass Spectrometers from Thomson and Aston to Present
International Journal of Mass Spectrometry 349–350 (2013) 9–18 Contents lists available at ScienceDirect International Journal of Mass Spectrometry j ournal homepage: www.elsevier.com/locate/ijms Development of mass spectrometers from Thomson and Aston to present a,b,∗ G. Münzenberg a GSI Helmholtzzentrum für Schwerionenforschung, Planckstrasse 1, 64291 Darmstadt, Germany b Manipal University, Manipal 576106, Karnataka, India a r a t i b s c t l e i n f o r a c t Article history: Mass spectrometry contributed to the understanding of the structure of elementary matter including Received 6 February 2013 the isotopic nature of the chemical elements, isotopic abundances, nuclear binding, and the investiga- Received in revised form 7 March 2013 tion of nuclides far-off stability. In this paper the continuous development of mass spectrometers from Accepted 11 March 2013 W. Wien’s first mass analysis to J.J. Thomson’s discovery of isotopes, F.W. Aston’s mass spectrometers, Available online 19 March 2013 and the Mattauch–Herzog double focusing spectrometer to the present rare isotope facilities will be dis- cussed. Separators with magnetic sector fields e.g. from A.O. Nier and the Oak Ridge separator batteries Keywords: for large-scale isotope production are included. The first applications to chemistry and geochemistry will Mass measurements be mentioned briefly. The key role of the development of ion optics from the first geometrical calcula- Sector mass spectrometers tions towards modern matrix method is addressed. Finally recent developments of mass spectrometers Historical developments for basic nuclear research including ISOL and in-flight separators for rare-isotope facilities and mass JEL classification: spectrometry with cooled and stored ions will be presented. -
Science and Scholasticism
JULY I, 1920] NATURE 547 Letters to the Editor. Science and Scholasticism. DR. SINGER'S review of my book ·• Medieval Medi (The_ )!ditor does not ho~d himself responsible for cine" in NATURE of April 1 has only just come under opinions expressed by his correspondents. Neither my notice. The mails separate us from England more can he undertake to return, or to correspond with than before the wc1r; may that be my excuse for a th~ write.rs of, rejected manuscripts intended for ?e!,ated word? l have nothing to say for the book, this or any other part of NATURE. No notice is 1t 1s thoroughly documented and must speak for itself; taken of anonymous communications.] but may I say a word for poor Aristotle and Hugo da Lucca, whom I have brought under the reviewer's The Constitution of the Elements. strictures? IN continuation of my letter in NATURE of March 4 Dr. Singer suggests that Aristotle has come into further experiments on mass-spectra have been made' appreciation again because we have found that he the results of which may be briefly announced a~ made observations on animal life. ls not the reason follows; rather that now that we ourselves have come to think Boron (atomic weight 10·9) is a complex element. through our observations to the principles beneath, we Its isotopes ar~ 10 and 11, satisfactorily confirmed by have found that Aristotle was usually before us? As sec_ond-order Imes at 5 and 5·5. Fluorine (atomic Prof. Wundt said, after spending a lifetime at experi weight 19-00) is apparently simple, as its chemical mental psychology: "It is only the animism of Aris atomic weight would lead one to expect. -
Dynamis-7 29.Indd
Making isotopes matter: Francis Aston and the mass-spectrograph Jeff Hughes Centre for the History of Science, Technology and Medicine. University of Manchester. [email protected] Dynamis Fecha de recepción: 22 de febrero de 2008 [0211-9536] 2009; 29: 131-165 Fecha de aceptación: 23 de julio de 2008 SUMMARY: 1.―Introduction. 2.―From bottlewasher to gentleman-researcher: Francis Aston at the Cavendish laboratory. 3.―Negotiating the nuclear atom: Rutherford, Bohr and Soddy. 4.―From positive rays to mass-spectrograph: Aston and the element of surprise. 5.―Ruther- ford, Aston and the constitutive role of the mass-spectrograph. 6.―The Nobel Prizes and the history of isotopes. 7.―Conclusion. ABSTRACT: Francis Aston «discovered» the isotopes of the light elements at the Cavendish Laboratory in 1919 using his newly devised mass-spectrograph. With this device, a modi- fication of the apparatus he had used as J.J. Thomson’s lab assistant before the war, Aston was surprised to find that he could elicit isotopes for many of the elements. This work was contested, but Rutherford, recently appointed to head the Cavendish, was a strong supporter of Aston’s work, not least because it supported his emergent programme of re- search into nuclear structure. This paper will explore Aston’s work in the context of skilled practice at the Cavendish and in the wider disciplinary contexts of physics and chemistry. Arguing that Aston’s work was made significant by Rutherford ―and other constituencies, including chemists and astrophysicists― it will explore the initial construction of isotopes as scientific objects through their embodiment in material practices.