Super-tomos Uma tabela peri³dica tridimensional? .Super-tomos Uma tabela peri³dica tridimensional?

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  • Super-tomos Uma tabela peridica tridimensional?

    Prof. Dr. Arnaldo Dal Pino JniorDep. de Fsica do ITA

  • Lavoisier divided the few elements known in the 1700's into classes.

  • John DaltonThe mass of an atom was it's most important property

    "The chemical elements are composed of... indivisible particles of matter, called atoms... atoms of the same element are identical in all respects, particularly weight." - Dalton

    Fsforo (P).

    Primeiro elemento a ser descoberto.

    Ponto de partida para a construo

    da tabela peridica".

  • Cloro, bromo e ido;

    A trade da primeira

    tentativa.

  • Periodic table begins with German chemist Johann Dobereiner (1780-1849) who grouped elements based on similarities.

    Dobereiner noticed the atomic weight of strontium fell midway between the weights of calcium and barium: Ca Sr Ba (40 + 137) 2 = 88

    coincidence? Dobereiner noticed the same pattern for the alkali metal triad (Li/Na/K) and the halogen triad (Cl/Br/I).

    Li Na K Cl Br I 7 23 39 35 80 127

    In 1829 Dobereiner proposed the Law of Triads: Middle element in the triad had atomic weight that was the average of the othertwo members.

    Soon other scientists found chemical relationships extended beyond triads. Fluorine was added to Cl/Br/I group; sulfur, oxygen, selenium and tellurium were grouped into a family; nitrogen, phosphorus, arsenic, antimony, and bismuth were classified as another group

  • Alexandre Beguyer de Chancourtois (1820-1886)

    professor of geology at the School of Mines in Paris recognized periodicity in the physical properties of the elements.

    1862 list of all the known elements.

    The list was constructed as a helical graph wrapped around a cylinder--elements with similar properties occupied positions on the same vertical line of cylinder (the list also included some ions and compounds). Using geological terms and published without the diagram, de Chancourtois ideas were completely ignored until the work of Mendeleev.

    First Periodic Table

  • Parafuso Telrico de Chancourtois

  • English chemist John Newlands (1837-1898), having arranged the 62 known elements in order of increasing atomic weights, noted that after interval of eight elements similar Physical /chemical properties reappeared.

    Newlands was the first to formulate the concept of periodicity in the properties of the chemical elements.

    Law of Octaves 1863

    In 1863 he wrote a paper proposing the Law of Octaves:

    Elements exhibit similar behavior to the eighth element following it in the table.

  • Ltio, potssio e sdio;

    pela primeira vez,

    juntos no modelo das

    oitavas de Newlands

  • In 1869, Russian chemist Dimitri Mendeleev (1834-1907) proposed arranging elements by atomic weights and properties.

    Mendeleev's periodic table of 1869 contained 17 columns with two partial periods of seven elements each (Li-F & Na-Cl) followed by two nearly complete periods (K-Br & Rb-I).

    In 1871 Mendeleev revised the 17-group table with eight columns (the eighth group consisted of transition elements). This table exhibited similarities not only in small units such as the triads, but showed similarities in an entire network of vertical, horizontal, and diagonal relationships.

    The table contained gaps but Mendeleev predicted the discovery of new elements. In 1906, Mendeleev came within one vote of receiving the Nobel Prize in chemistry.

    Mendeleev's Periodic Table

  • Em 1869, enquanto escrevia seu livro de qumica inorgnica, organizou os elementos na forma da tabela peridica atual. Mendeleev criou uma carta para cada um dos 63 elementosconhecidos.

    Cada carta continha o smbolo do elemento, a massa atmica e suas propriedades qumicas e fsicas.

    Colocando as cartas em uma mesa, organizou-as em ordem crescente de suas massas atmicas, agrupando-as em elementos de propriedades semelhantes. Formou-se ento a tabela peridica.

  • Julius Lothar Meyer (1830 - 1895).

    Em 1869, Meyer e Mendeleyev, trabalhando independentemente, lanaram classificaes peridicas semelhantes. Mas o brilhantismo das previses de Mendeleyev ofuscou por completo o resultado das pesquisas de Lothar Meyer.

    Em 1882, porm, os dois cientistas receberam a Medalha Davy, a mais alta honraria da Associao Britnica para o Progresso da Cincia.

    Vale lembrar tambm que, em 1887, outra injustia foi reparada. A mesma medalha foi oferecida a Newlands, o cientista que fora ridicularizado por sua classificao baseada nas oitavas musicais.

  • O cientista russo deixou alguns espaos vagos na sua tabela, justificando que esses locais eram reservados para o eventual ordenamento de elementos, na poca, ainda desconhecidos, denominando-os de:

    Eka-boro (abaixo do boro);Eka-aluminio (abaixo do aluminio);Eka-silcio (abaixo do silcio).

    Demonstrando grande sagacidade cientfica, Mendeleyev definiu as propriedades desses elementos ainda desconhecidos.

    A consagrao de Mendeleyev

  • Suas previses se mostraram corretas:

    em 1874, o Eka-alumnio foi descoberto por L. Boisbaudran, recebendo o nome de Glio;

    cinco anos depois, Lars F. Nilson descobriu o Eka-boro, cuja denominao passou a ser de Escndio;

    finalmente, em 1886, Clemens Alexander Winkler descobriu o Eka-silcio, elemento hoje denominado de Germnio.

    Para melhor compreenso, observe:

    Previses

  • A tabela abaixo mostra as propriedades do germnio e as propriedades previstas por Mendeleev para esse elemento, que na poca era desconhecido e o qual Mendeleev nomeou de eka-silcio.

    4,74,74,74,7Densidade Densidade xidoxido

    Cinza claroCinza claroCinzentoCinzentoCorCor

    5.475.475,505,50Densidade(Densidade(g/cg/cmm33))

    72,672,67272Massa AtmicaMassa Atmica

    GermnioGermnioEkaEka--SilSilciocioPropriedadesPropriedades

  • A tabela abaixo mostra as propriedades do germnio e as propriedades previstas por Mendeleev para esse elemento, que na poca era desconhecido e o qual Mendeleev nomeou de eka-alumnio.

    GaGa22OO33((EAlEAl))22OO33xidoxido

    30,15 30,15 00CCBaixoBaixoPtoPto. de Fuso. de Fuso

    5.945.945,95,9Densidade(Densidade(g/cg/cmm33))

    69,769,76868Massa AtmicaMassa Atmica

    GGliolioEkaEka--AlumAlumnionioPropriedadesPropriedades

  • In 1895 Rayleigh reported the discovery of a new gaseous element named argon. This element was chemically inert and did not fit any of the known periodic groups.

    Ramsey followed by discovering the remainder of the inert gases and positioning them in the periodic table.

    So by 1900, the periodic table was taking shape with elements were arranged by atomic weight. For example, 16g oxygen reacts with 40g calcium, 88g strontium, or 137g barium.

    Rayleigh (physics) and Ramsey (chemistry) were awarded Nobel prizes in 1904. The first inert gas compound was made in 1962 (xenon tetrafluoride) and numerous compounds have followed

    Lord Rayleigh (1842-1919)

    William Ramsey (1852-1916)

  • When Moseley arranged the elements according to increasing atomic numbers and not atomic masses, some of the inconsistencies associated with Mendeleev's table were eliminated. The modern periodic table is based on Moseley's Periodic Law (atomic numbers).

    At age 28, Moseley was killed in action during World War I and as a direct result Britain adopted the policy of exempting scientists from fighting in wars. Shown below is a periodic table from 1930:

    Moseley's Periodic Law

    Soon after Rutherford's landmark experiment of discovering the proton in 1911, Henry Moseley (1887-1915) subjected known elements to x-rays. He was able to derive the relationship between x-ray frequency and number of protons.

  • 1872 - A tabela peridica de Mendeleyev.Os espaos marcados com traos representam elementos que Mendeleyev deduziuexistirem mas que ainda no haviam sido descobertos quela poca. Os smbolos no topo de cada coluna so as frmulas moleculares escritas no estilo do sculo XIX.

  • The last major change to the periodic table resulted from Glenn Seaborg's work in the middle of the 20th century. Starting with plutonium in 1940, Seaborg discovered transuranium elements 94 to 102 and reconfigured the periodic table by placing the lanthanide/actinide series at the bottom of the table. In 1951 Seaborg was awarded the Nobel Prize in chemistry and element 106 was later named seaborgium (Sg) in his honor.

    Modern Periodic Table

  • Dr. Timmothy Stowe's physicists periodic table.

  • The periodic spiral of Professor Theodor Benfey

  • A triangular long form periodic table by Emil Zmaczynski.

  • Superatoms

    Superatoms are clusters of atoms which seem to exhibit some of the properties of elemental atoms.

    Sodium atoms when left to condense in clusters from vapournaturally form into clusters of 8, 20, 40, 58 or 92 atoms (the magic numbers).

    The suggestion is that free electrons in the cluster form atomic like structure

    The atomic properties of this structure should mimic the atomic properties of atoms with filled s and p orbitals, i.e. the noble gases.

  • Jellium is the theory of interacting electrons in which a uniform background of positive charge exists. In this theory at zero temperature the system properties are dependent only on the density of electrons.

    This allows for the simplistic calculation of the electron-electron coupling energy being a ratio between the free-electron kinetic energy and the Coulomb potential energy.

    The jellium theory is used in nuclear physics. It has been used to try to explai