Physical Properties of Noble Gases
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Identification of a Chemical Fingerprint Linking the Undeclared 2017 Release of 106Ru to Advanced Nuclear Fuel Reprocessing
Identification of a chemical fingerprint linking the undeclared 2017 release of 106Ru to advanced nuclear fuel reprocessing Michael W. Cookea,1, Adrian Bottia, Dorian Zokb, Georg Steinhauserb, and Kurt R. Ungara aRadiation Protection Bureau, Health Canada, Ottawa, ON K1A 1C1, Canada; and bInstitute of Radioecology and Radiation Protection, Leibniz Universität Hannover, 30419 Hannover, Germany Edited by Kristin Bowman-James, University of Kansas, Lawrence, KS, and accepted by Editorial Board Member Marcetta Y. Darensbourg May 1, 2020 (received for review February 7, 2020) The undeclared release and subsequent detection of ruthenium- constitutes the identification of unique signatures. From a radiologi- 106 (106Ru) across Europe from late September to early October of cal perspective, there is none. Samples have been shown to be radi- 2017 prompted an international effort to ascertain the circum- opure and to carry the stable ruthenium isotopic signature of civilian stances of the event. While dispersion modeling, corroborated spent nuclear fuel (10), while stable elemental analysis by scanning by ground deposition measurements, has narrowed possible loca- electron microscopy and neutron activation has revealed no detect- tions of origin, there has been a lack of direct empirical evidence to able anomalies compared to aerosol filter media sampled prior to the address the nature of the release. This is due to the absence of advent of the 106Ru contaminant (1, 11). We are, then, left with the radiological and chemical signatures in the sample matrices, con- definition of a limiting case for a nuclear forensic investigation. sidering that such signatures encode the history and circumstances Fortunately, we are concerned with an element that has sig- of the radioactive contaminant. -
Entropy: Ideal Gas Processes
Chapter 19: The Kinec Theory of Gases Thermodynamics = macroscopic picture Gases micro -> macro picture One mole is the number of atoms in 12 g sample Avogadro’s Number of carbon-12 23 -1 C(12)—6 protrons, 6 neutrons and 6 electrons NA=6.02 x 10 mol 12 atomic units of mass assuming mP=mn Another way to do this is to know the mass of one molecule: then So the number of moles n is given by M n=N/N sample A N = N A mmole−mass € Ideal Gas Law Ideal Gases, Ideal Gas Law It was found experimentally that if 1 mole of any gas is placed in containers that have the same volume V and are kept at the same temperature T, approximately all have the same pressure p. The small differences in pressure disappear if lower gas densities are used. Further experiments showed that all low-density gases obey the equation pV = nRT. Here R = 8.31 K/mol ⋅ K and is known as the "gas constant." The equation itself is known as the "ideal gas law." The constant R can be expressed -23 as R = kNA . Here k is called the Boltzmann constant and is equal to 1.38 × 10 J/K. N If we substitute R as well as n = in the ideal gas law we get the equivalent form: NA pV = NkT. Here N is the number of molecules in the gas. The behavior of all real gases approaches that of an ideal gas at low enough densities. Low densitiens m= enumberans tha oft t hemoles gas molecul es are fa Nr e=nough number apa ofr tparticles that the y do not interact with one another, but only with the walls of the gas container. -
On the Equation of State of an Ideal Monatomic Gas According to the Quantum-Theory, In: KNAW, Proceedings, 16 I, 1913, Amsterdam, 1913, Pp
Huygens Institute - Royal Netherlands Academy of Arts and Sciences (KNAW) Citation: W.H. Keesom, On the equation of state of an ideal monatomic gas according to the quantum-theory, in: KNAW, Proceedings, 16 I, 1913, Amsterdam, 1913, pp. 227-236 This PDF was made on 24 September 2010, from the 'Digital Library' of the Dutch History of Science Web Center (www.dwc.knaw.nl) > 'Digital Library > Proceedings of the Royal Netherlands Academy of Arts and Sciences (KNAW), http://www.digitallibrary.nl' - 1 - 227 high. We are uncertain as to the cause of this differencc: most probably it is due to an nncertainty in the temperature with the absolute manometer. It is of special interest to compare these observations with NERNST'S formula. Tbe fourth column of Table II contains the pressUl'es aceord ing to this formula, calc111ated witb the eonstants whieb FALCK 1) ha~ determined with the data at bis disposal. FALOK found the following expression 6000 1 0,009983 log P • - --. - + 1. 7 5 log T - T + 3,1700 4,571 T . 4,571 where p is the pressure in atmospheres. The correspondence will be se en to be satisfactory considering the degree of accuracy of the observations. 1t does riot look as if the constants could be materially improved. Physics. - "On the equation of state oj an ideal monatomic gflS accoJ'ding to tlw quantum-the01'Y." By Dr. W. H. KEEsmr. Supple ment N°. 30a to the Oommunications ft'om the PhysicaL Labora tory at Leiden. Oommunicated by Prof. H. KAl\IERLINGH ONNES. (Communicated in the meeting of May' 31, 1913). -
Periodic Trends in the Main Group Elements
Chemistry of The Main Group Elements 1. Hydrogen Hydrogen is the most abundant element in the universe, but it accounts for less than 1% (by mass) in the Earth’s crust. It is the third most abundant element in the living system. There are three naturally occurring isotopes of hydrogen: hydrogen (1H) - the most abundant isotope, deuterium (2H), and tritium 3 ( H) which is radioactive. Most of hydrogen occurs as H2O, hydrocarbon, and biological compounds. Hydrogen is a colorless gas with m.p. = -259oC (14 K) and b.p. = -253oC (20 K). Hydrogen is placed in Group 1A (1), together with alkali metals, because of its single electron in the valence shell and its common oxidation state of +1. However, it is physically and chemically different from any of the alkali metals. Hydrogen reacts with reactive metals (such as those of Group 1A and 2A) to for metal hydrides, where hydrogen is the anion with a “-1” charge. Because of this hydrogen may also be placed in Group 7A (17) together with the halogens. Like other nonmetals, hydrogen has a relatively high ionization energy (I.E. = 1311 kJ/mol), and its electronegativity is 2.1 (twice as high as those of alkali metals). Reactions of Hydrogen with Reactive Metals to form Salt like Hydrides Hydrogen reacts with reactive metals to form ionic (salt like) hydrides: 2Li(s) + H2(g) 2LiH(s); Ca(s) + H2(g) CaH2(s); The hydrides are very reactive and act as a strong base. It reacts violently with water to produce hydrogen gas: NaH(s) + H2O(l) NaOH(aq) + H2(g); It is also a strong reducing agent and is used to reduce TiCl4 to titanium metal: TiCl4(l) + 4LiH(s) Ti(s) + 4LiCl(s) + 2H2(g) Reactions of Hydrogen with Nonmetals Hydrogen reacts with nonmetals to form covalent compounds such as HF, HCl, HBr, HI, H2O, H2S, NH3, CH4, and other organic and biological compounds. -
Ideal Gasses Is Known As the Ideal Gas Law
ESCI 341 – Atmospheric Thermodynamics Lesson 4 –Ideal Gases References: An Introduction to Atmospheric Thermodynamics, Tsonis Introduction to Theoretical Meteorology, Hess Physical Chemistry (4th edition), Levine Thermodynamics and an Introduction to Thermostatistics, Callen IDEAL GASES An ideal gas is a gas with the following properties: There are no intermolecular forces, except during collisions. All collisions are elastic. The individual gas molecules have no volume (they behave like point masses). The equation of state for ideal gasses is known as the ideal gas law. The ideal gas law was discovered empirically, but can also be derived theoretically. The form we are most familiar with, pV nRT . Ideal Gas Law (1) R has a value of 8.3145 J-mol1-K1, and n is the number of moles (not molecules). A true ideal gas would be monatomic, meaning each molecule is comprised of a single atom. Real gasses in the atmosphere, such as O2 and N2, are diatomic, and some gasses such as CO2 and O3 are triatomic. Real atmospheric gasses have rotational and vibrational kinetic energy, in addition to translational kinetic energy. Even though the gasses that make up the atmosphere aren’t monatomic, they still closely obey the ideal gas law at the pressures and temperatures encountered in the atmosphere, so we can still use the ideal gas law. FORM OF IDEAL GAS LAW MOST USED BY METEOROLOGISTS In meteorology we use a modified form of the ideal gas law. We first divide (1) by volume to get n p RT . V we then multiply the RHS top and bottom by the molecular weight of the gas, M, to get Mn R p T . -
Thermodynamics Molecular Model of a Gas Molar Heat Capacities
Thermodynamics Molecular Model of a Gas Molar Heat Capacities Lana Sheridan De Anza College May 7, 2020 Last time • heat capacities for monatomic ideal gases Overview • heat capacities for diatomic ideal gases • adiabatic processes Quick Recap For all ideal gases: 3 3 K = NK¯ = Nk T = nRT tot,trans trans 2 B 2 and ∆Eint = nCV ∆T For monatomic gases: 3 E = K = nRT int tot,trans 2 and so, 3 C = R V 2 and 5 C = R P 2 Reminder: Kinetic Energy and Internal Energy In a monatomic gas the three translational motions are the only degrees of freedom. We can choose 3 3 E = K = N k T = nRT int tot,trans 2 B 2 (This is the thermal energy, so the bond energy is zero { if we liquify the gas the bond energy becomes negative.) Equipartition Consequences in Diatomic Gases Reminder: Equipartition of energy theorem Each degree of freedom for each molecule contributes an and 1 additional 2 kB T of energy to the system. A monatomic gas has 3 degrees of freedom: it can have translational KE due to motion in 3 independent directions. A diatomic gas has more ways to move and store energy. It can: • translate • rotate • vibrate 21.3 The Equipartition of Energy 635 Equipartition21.3 The Equipartition Consequences of Energy in Diatomic Gases Predictions based on our model for molar specific heat agree quite well with the Contribution to internal energy: Translational motion of behavior of monatomic gases, but not with the behavior of complex gases (see Table the center of mass 21.2). -
The Noble Gases
INTERCHAPTER K The Noble Gases When an electric discharge is passed through a noble gas, light is emitted as electronically excited noble-gas atoms decay to lower energy levels. The tubes contain helium, neon, argon, krypton, and xenon. University Science Books, ©2011. All rights reserved. www.uscibooks.com Title General Chemistry - 4th ed Author McQuarrie/Gallogy Artist George Kelvin Figure # fig. K2 (965) Date 09/02/09 Check if revision Approved K. THE NOBLE GASES K1 2 0 Nitrogen and He Air P Mg(ClO ) NaOH 4 4 2 noble gases 4.002602 1s2 O removal H O removal CO removal 10 0 2 2 2 Ne Figure K.1 A schematic illustration of the removal of O2(g), H2O(g), and CO2(g) from air. First the oxygen is removed by allowing the air to pass over phosphorus, P (s) + 5 O (g) → P O (s). 20.1797 4 2 4 10 2s22p6 The residual air is passed through anhydrous magnesium perchlorate to remove the water vapor, Mg(ClO ) (s) + 6 H O(g) → Mg(ClO ) ∙6 H O(s), and then through sodium hydroxide to remove 18 0 4 2 2 4 2 2 the carbon dioxide, NaOH(s) + CO2(g) → NaHCO3(s). The gas that remains is primarily nitrogen Ar with about 1% noble gases. 39.948 3s23p6 36 0 The Group 18 elements—helium, K-1. The Noble Gases Were Kr neon, argon, krypton, xenon, and Not Discovered until 1893 83.798 radon—are called the noble gases 2 6 4s 4p and are noteworthy for their rela- In 1893, the English physicist Lord Rayleigh noticed 54 0 tive lack of chemical reactivity. -
Argon: Systematic Review on Neuro- and Organoprotective Properties of an “Inert” Gas
Int. J. Mol. Sci. 2014, 15, 18175-18196; doi:10.3390/ijms151018175 OPEN ACCESS International Journal of Molecular Sciences ISSN 1422-0067 www.mdpi.com/journal/ijms Review Argon: Systematic Review on Neuro- and Organoprotective Properties of an “Inert” Gas Anke Höllig 1,2, Anita Schug 1, Astrid V. Fahlenkamp 2, Rolf Rossaint 2, Mark Coburn 2,* and Argon Organo-Protective Network (AON) † 1 Department of Neurosurgery, University RWTH Aachen, 52074 Aachen, Germany; E-Mails: [email protected] (A.H.); [email protected] (A.S.) 2 Department of Anesthesiology, University RWTH Aachen, 52074 Aachen, Germany; E-Mails: [email protected] (A.V.F.); [email protected] (R.R.) † Members are listed in Appendix. * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +49-241-80-88179; Fax: +49-241-80-82406. External Editor: Katalin Prokai-Tatrai Received: 14 August 2014; in revised form: 12 September 2014 / Accepted: 23 September 2014 / Published: 10 October 2014 Abstract: Argon belongs to the group of noble gases, which are regarded as chemically inert. Astonishingly some of these gases exert biological properties and during the last decades more and more reports demonstrated neuroprotective and organoprotective effects. Recent studies predominately use in vivo or in vitro models for ischemic pathologies to investigate the effect of argon treatment. Promising data has been published concerning pathologies like cerebral ischemia, traumatic brain injury and hypoxic ischemic encephalopathy. However, models applied and administration of the therapeutic gas vary. Here we provide a systematic review to summarize the available data on argon’s neuro- and organoprotective effects and discuss its possible mechanism of action. -
Chapter 10 100 Years of Progress in Gas-Phase Atmospheric Chemistry Research
CHAPTER 10 WALLINGTON ET AL. 10.1 Chapter 10 100 Years of Progress in Gas-Phase Atmospheric Chemistry Research T. J. WALLINGTON Research and Advanced Engineering, Ford Motor Company, Dearborn, Michigan J. H. SEINFELD California Institute of Technology, Pasadena, California J. R. BARKER Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, Michigan ABSTRACT Remarkable progress has occurred over the last 100 years in our understanding of atmospheric chemical composition, stratospheric and tropospheric chemistry, urban air pollution, acid rain, and the formation of airborne particles from gas-phase chemistry. Much of this progress was associated with the developing un- derstanding of the formation and role of ozone and of the oxides of nitrogen, NO and NO2, in the stratosphere and troposphere. The chemistry of the stratosphere, emerging from the pioneering work of Chapman in 1931, was followed by the discovery of catalytic ozone cycles, ozone destruction by chlorofluorocarbons, and the polar ozone holes, work honored by the 1995 Nobel Prize in Chemistry awarded to Crutzen, Rowland, and Molina. Foundations for the modern understanding of tropospheric chemistry were laid in the 1950s and 1960s, stimulated by the eye-stinging smog in Los Angeles. The importance of the hydroxyl (OH) radical and its relationship to the oxides of nitrogen (NO and NO2) emerged. The chemical processes leading to acid rain were elucidated. The atmosphere contains an immense number of gas-phase organic compounds, a result of emissions from plants and animals, natural and anthropogenic combustion processes, emissions from oceans, and from the atmospheric oxidation of organics emitted into the atmosphere. -
Physics 1401 - Final Exam Chapter 13 Review
Physics 1401 - Final Exam Chapter 13 Review 11. The coefficient of linear expansion of steel is 12 ⋅ 10 –6/C°. A railroad track is made of individual rails of steel 1.0 km in length. By what length would these rails change between a cold day when the temperature is –10 °C and a hot day at 30 °C? (a) 0.62 cm (c) 48 cm (e) 620 cm (b) 24 cm (d) 480 cm 12. The coefficient of linear expansion of aluminum is 23 ⋅ 10 –6/C°. A circular hole in an aluminum plate is 2.725 cm in diameter at 0 °C. What is the diameter of the hole if the temperature of the plate is raised to 100 C? (a) 0.0063 cm (c) 2.731 cm (e) 2.788 cm (b) 2.728 cm (d) 2.757 cm 14 . A copper plate has a length of 0.12 m and a width of 0.10 m at 25 °C. The plate is uniformly heated to 175 °C. If the linear expansion coefficient for copper is 1.7 ⋅ 10 –5/C°, what is the change in the area of the plate as a result of the increase in temperature? (a) 2.6 ⋅ 10 –5 m2 (c) 3.2 ⋅ 10 –6 m2 (e) 7.8 ⋅ 10 –7 m2 (b) 6.1 ⋅ 10 –5 m2 (d) 4.9 ⋅ 10 –7 m2 Review Final Exam-New .doc - 1 - 17 . A steel string guitar is strung so that there is negligible tension in the strings at a temperature of 24.9 °C. -
Chemistry 20 – Lesson 2 Atoms, Ions, Compounds /100 Part 1 Group 1 18 Group IA VIIIA
Chemistry 20 – Lesson 2 Atoms, ions, compounds /100 Part 1 Group 1 18 Group IA VIIIA 1 2 1e– 2 13 14 15 16 17 2e– 1p+ 2p+ hydrogen IIA IIIA IVA VA VIA VIIA helium H He 3 – 4 – 5 – 6 – 7 – 8 – 9 – 10 – 1e 2e 3e 4e 5e 6e 7e 8e – – – – – – – – 2e 2e 2e 2e 2e 2e 2e 2e 3 p+ 4p+ 5p+ 6p+ 7p+ 8p+ 9p+ 10p+ lithium beryllium boron carbon nitrogen oxygen fluorine neon Li Be B C N O F Ne 11 1e– 12 2e– 13 3e– 14 4e– 15 5e– 16 6e– 17 7e– 18 8e– – – – – – – – – 8e 8e 8e 8e 8e 8e 8e 8e – – – – – – – – 2e 2e 2e 2e 2e 2e 2e 2e 11p+ 12p+ 13p+ 14p+ 15p+ 16p+ 17p+ 18p+ sodium magnesium aluminum silicon phosphorous sulfur chlorine argon Na Mg Al Si P S Cl Ar Questions: 1. What is the relationship between the old American system group number and the number of valence electrons? The roman numeral matches the number of valence electrons. 2. What is the relationship between the period number and the number of energy levels in which electrons are accommodated? The period number is the same as the number of electron energy levels for the atoms in the period. 3. What is the relationship between the maximum number of electrons in each energy level and the number of atoms in each period of the periodic table? The number of atoms in a period equals the maximum number of electrons that can exist at that energy level. 4. According to the above abbreviated periodic table, how many electrons can be accommodated before a new energy level is started in each of the first three energy levels? 1st energy level 2 2nd energy level 8 3rd energy level 8 5. -
Partition Functions and Ideal Gases PFIG-1
Partition Functions and Ideal Gases PFIG-1 You’ve learned about partition functions and some uses, now we’ll explore them in more depth using ideal monatomic, diatomic and polyatomic gases! Before we start, remember: N q(,) V T What are N, V, and T? QNVT(,,)= N! We now apply this to the ideal gas where: 1. The molecules are independent. 2. The number of states greatly exceeds the number of low pressure).fssumption omolecules (a Ideal monatomic gases PFIG-2 Where can we put energy into a monatomic gas? ε atomic = ε trans + ε elec Only into translational and electronic modes! ☺ The total partition function is the product of the partition functions from each degree of freedom: q V(,)(,)(,) T q= trans V Telec q V T Total atomic Translational atomic Electronic atomic partition function partition function partition function We’ll consider both separately… Translations of Ideal Gas:qtrans(,) V T PFIG-3 −βε trans General form of partition function:qtrans = ∑ e states z QM slides…Recall from c b x a 2 h 2 2 2 ε = n( + n + ) n,n ,x n y 1 nz= , 2∞ ,..., trans 8ma2 x y z So what is qtrans? Let’s simplify qtrans … PFIG-4 ∞ ∞ ∞ ∞ 2 −βε nx,,ny nz ⎡ βh 2 2 2⎤ qtrans = e = exp⎢− n2 ()x+ n y + nz⎥ ∑ ∑ ∑ ∑8ma nx, n y , n= z 1 nx1= n y= 1 n = z1 ⎣ ⎦ a b+ c + a b c Recall:e = e e e ∞ ⎛ βh2 n 2⎞ ∞ ⎛ βh2 n 2⎞ ∞ ⎛ βh2 n 2⎞ q =exp⎜ − x ⎟ exp⎜− y ⎟ exp⎜− z ⎟ trans ∑ ⎜ 8ma2 ⎟∑ ⎜ 8ma2 ⎟∑ ⎜ 8ma2 ⎟ nx =1 ⎝ ⎠ny =1 ⎝ ⎠nz =1 ⎝ ⎠ All three sums are the same because nx, ny, nz have same form! We can simplify expression to: qtrans is nearly continuous PFIG-5 3 We’d like