Nuclear Chemistry Sound Records Sound Records: Radioactivity Chemical Elements General Chemistry Vocabulary Brno 2014 Radioactivity Radioactivity was discovered in 1896 by the French scientist Henri Becquerel, while working on phosphorescent materials. These materials glow in the dark after exposure to light, and he suspected that the glow produced in cathode ray tubes by X-rays might be associated with phosphorescence. He wrapped a photographic plate in black paper and placed various phosphorescent salts on it. All results were negative until he used uranium salts. The result with these compounds was to cause a blackening of the plate in spite of the plate being wrapped in black paper. These radiations were given the name "Becquerel Rays". It soon became clear that the blackening of the plate had nothing to do with phosphorescence, as the plate recorded the presence of the mineral while wrapped and non-phosphorescent salts of uranium and metallic uranium also blackened the plate. It was clear that there was a form of invisible radiation that could pass through paper and was causing the plate to react as if exposed to light and so become black. At first, it seemed as though the new radiation was similar to the then recently discovered X-rays. Further research by Becquerel, Ernest Rutherford, Paul Villard, Pierre Curie, Marie Curie, and others showed that this form of radioactivity was significantly more complicated. Rutherford was the first to realize that they all decay in accordance with the same mathematical exponential formula, and Rutherford and his student Frederick Soddy were the first to realize that many decay processes resulted in the transmutation of one element to another. Subsequently, the radioactive displacement law of Fajans and Soddy was formulated to describe the products of alpha and beta decay. The early researchers also discovered that many other chemical elements, besides uranium, have radioactive isotopes. A systematic search for the total radioactivity in uranium ores also guided Pierre and Marie Curie to isolate two new elements: polonium and radium. Except for the radioactivity of radium, the chemical similarity of radium to barium made these two elements difficult to distinguish. The dangers of radioactivity and radiation were not immediately recognized. The discovery of x‑rays in 1895 led to widespread experimentation by scientists, physicians, and inventors. Many people began recounting stories of burns, hair loss and worse in technical journals as early as 1896. In February of that year, Professor Daniel and Dr. Dudley of Vanderbilt University performed an experiment involving x-raying Dudley's head that resulted in his hair loss. A report by Dr. H.D. Hawks, a graduate of Columbia College, of his suffering severe hand and chest burns in an x-ray demonstration, was the first of many other reports in Electrical Review. Many experimenters including Elihu Thomson at Thomas Edison's lab, William J. Morton, and Nikola Tesla also reported burns. Elihu Thomson deliberately exposed a finger to an x-ray tube over a period of time and suffered pain, swelling, and blistering. Other effects, including ultraviolet rays and ozone were sometimes blamed for the damage. Many physicians claimed that there were no effects from x-ray exposure at all. Before the biological effects of radiation were known, many physicians and corporations began marketing radioactive substances as patent medicine in the form of glow-in-the-dark pigments. Examples were radium enema treatments, and radium-containing waters to be drunk as tonics.Marie Curie protested against this sort of treatment, warning that the effects of radiation on the human body were not well understood. Curie later died from aplastic anaemia, likely caused by exposure to ionizing radiation. By the 1930s, after a number of cases of bone necrosis and death of radium treatment enthusiasts, radium-containing medicinal products had been largely removed from the market (radioactive quackery). Chemical Elements Actinium Aluminium Aluminum Americium Antimony Argon Arsenic Astatine Barium Berkelium Beryllium Bismuth Bohrium Boron Bromine Cadmium Caesium Calcium Californium Carbon Cerium Cesium Chlorine Chromium Cobalt Copernicium Copper Curium Darmstadtium Dubnium Dysprosium Einsteinium Erbium Europium Fermium Flerovium Fluorine Francium Gadolinium Gallium Germanium Gold Hafnium Hassium Helium Holmium Hydrogen Indium Iodine Iridium Iron Krypton Lanthanum Lawrencium Lead Lithium Livermorium Lutetium Magnesium Manganese Meitnerium Mendelevium Mercury Molybdenum Neodymium Neon Neptunium Nickel Niobium Nitrogen Nobelium Osmium Oxygen Palladium Phosphorus Platinum Plutonium Polonium Potassium Praseodymium Promethium Protactinium Radium Radon Rhenium Rhodium Roentgenium Rubidium Ruthenium Rutherfordium Samarium Scandium Seaborgium Selenium Silicon Silver Sodium Strontium Sulphur Tantalum Technetium Tellurium Terbium Thallium Thorium Thulium Tin Titanium Tungsten Ununoctium Ununpentium Ununseptium Ununtrium Uranium Vanadium Xenon Ytterbium Yttrium Zinc Zirconium General Vocabulary absorbance absorption of radiation electron affinity actinides a-helix aluminosilicate volumetric analysis gravimetric analysis aniline antiparticle activation barrier baryon soft base hard base benzene protein biochemistry stationary point borane boson intermediate boson butadiene reaction path a particle b particle particle of force field atomic number Avogadro´s number quantum number principal quantum number magnetic quantum number orbital angular momentum quantum number mass number proton number degenaracy of state bond lenght wavelength derivative deuterium diffusion dissociation particle-wave duality nonadiabatic effect electrolyte strong electrolyte weak electrolyte elektrolysis electron electronegativity emission of radiation energy activation energy total energy discrimination energy dissociation energy photon energy Gibbs (free) energy standard Gibbs energy Helmholtz energy kinetic energy zero-point energy orbital energy potential energy potential energy curve vibrational energy internal energy enthalpy enthalpy of reaction standard enthalpy of formation entropy enzyme ethylene fermion fluidity fluorescence phosphorescence photon collision frequency frequency of radiation function state function wave function symmetry properties of wave function electron wave function nuclear fusion gene geometry of molecule graphite graviton group point group hadron Hamiltonian helium atomic mass molecular mass electron density, distribution probability density (linear) momentum hybridization potential energy hypersurface analytical chemistry inorganic chemistry physical chemistry organic chemistry chirality chromatography chromosome angular momentum genetic information graphical integration numerical integration integral indefinite integral constant of motion overlap integral definite integral Coulomb interaction electromagnetic interaction gravitational interaction strong interaction weak interaction hydrogen molecular ion insulator isomer atomic nucleus carcinogenic activity of hydrocarbons heat capacity catalysis acid catalysis hydronium cation cluster molar absorption coefficient expansion coefficient activated complex transition complex charge-transfer complex electron configuration dissociation constant Planck constant (universal) gas constant equilibrium constant rate constant energy continuum reaction coordinate ionic crystal liquid crystal covalent crystal molecular crystal potential-energy curve quantization quantization of energy quark deoxyribonucleic acid soft acid nucleic acid hard acid lanthanides laser amorphous solids crystalline solids lepton ligand classical mechanics statistical mechanics donor-acceptor mechanism reaction mechanism metallocene metalloid reaction intermediate meson muon amount of substance antibonding MO bonding MO cyclic molecule molecularity of reaction angular momentum orbital angular momentum magnetic moment transition moment spin multiplicity naphtalene nonmetal indistinguishability of particles neutralization neutrino neutron nucleoside nucleotide nuclide molar volume inversion (operation) symmetry operation operator Hamilton operator (Hamiltonian) Laplace operator (Laplacian) atomic orbital hybrid orbital molecular orbital unoccupied (virtual) orbital occupied orbital valence orbital p orbital d orbital s orbital symmetry axis electron pair absorption band energy band valence band conduction band period (row) of elements permittivity (dielectric constant) pH, measure of acidity ideal gas real gas synthesis gas noble gas boundary condition initial condition computational experiment polarography half-life for radioactive decay semiconductor bathochromic shift hypsochromic shift ionization potential positron Hund rule rule of maximum multiplicity selection rule Heisenberg uncertainty principle building-up (Aufbau) principle principle of equipartition of energy Pauli exclusion principle absorption process adiabatic process emission process irreversible process reversible process product of reaction ion product constant of water proton transition element symmetry element spectral transition pyridine radical induced radioactivity spontaneous radioactivity bimolecular reaction endothermic reaction exothermic reaction photochemical reaction monomolecular (unimolecular) reaction first-order reaction reduction-oxidation reaction kinetically controlled reaction thermodynamically controlled reaction trimolecular (termolecular) reaction reactant reduction Coulomb repulsion rotation Clausius-Clapeyron equation differential equation equation of state for the ideal gas van der Waals equation acid-base equilibrium catalytic decomposition radioactive decay reaction rate decay rate velocity of light reaction order orbital scheme state scheme intermolecular forces physical state group of elements conjugated compound nonstoichiometric compound electron shell closed shell solvolysis spectrometer mass spectrometry infrared spectroscopy microwave spectroscopy electronic spectrum rotational spectrum vibrational- rotational spectrum spin elastic collision inelastic collision reactive collision electronic state liquid state quantum state state of a substance solid (state) gaseous state resonance phenomenon rotational state equilibrium singlet state stationary state standard state excited state ground state stoichiometry molecular structure centre of symmetry degree of degeneracy vibrational degree of freedom superconductivity symmetry nuclear fission Bohr theory quantum theory collision theory heat heat of sublimation heat of vaporization absolute (Kelvin) temperature thermodynamics chemical thermodynamics thiophene system trajectory tritium mass defect dihedral angle bond angle aliphatic hydrocarbon alternant hydrocarbon cyclic hydrocarbon saturated hydrocarbon nonalternant hydrocarbon unsaturated hydrocarbon double bond chemical bond peptide bond triple bond hydrogen bond vibration vibration of a bond viscosity extensive property intensive property conductor electron shell Einstein relation weakon Hess law Lambert-Beer law Maxwell-Boltzmann energy-distribution law law of conservation of energy electromagnetic radiation zeolite reflection