atomic theory timeline

By alexbaird

  • John Dalton

    In 1803, Dalton had discovered the atomic theory.This theory was based off of Daltons Law - saying when different gasses combine, with the final pressure will be the sum of each gas gives individually. His theory proposed these basic ideas: all mater is composed of atoms, atoms cannot be created or destroyed, all atoms of the same element are identical, different elements have different types of atoms, and chemical reactions occure when atoms are rearranged (2013 hysis prize. para 3).

  • James Clerk Maxwell

    proposed that electric waves including magnetic waves, has been filled with a void. he also translated Faradays theories into mathmadical formats of equations. He also copied the quipartition theorem and tried to describe spectral lines using a vibration model (timeline of the atom para. 11)

  • Sir Williams Crookes

    Crookes advanced the atomic theory. He came up with the Cathode Rays. He also discovered that these rays are more in a straight line, causeing glass to glow carry. change and capable of being deflected by electric field. ( timeline of the atom par 12)

  • JJ Thomson

    Thomson got rid of the concept of heavy solids and absolute invisibale atoms and replaced them with the concept that the atoms was made up of smaller particles. His Discovery came from the study of the Cathode ray. the fraction of the atom beca,e known as the electron.( timeline of the atom para. 15 ).

  • Marie Curie

    Curie Defines modern knowledge of the radioactice process. Curie also created the term "radioactivity" first to identify isolate and study the properties of two important radioactive elements: radium and polonium ( timeline of the atom para 16).

  • Max Planck

    Planck didnt understand the radioactivity process, how the distribution of the energy during radioactivity process. He then discovered the relationship between the energy and the frequency of radiation ( timeline of the atom para. 17).

  • Otto Hahn

    Hahn Discovered the mesothorium. He also disovere the athifically active uranium isotope.And he lter discoverd uranium Z (Nobelprize. para. 5,7-9).

  • R.A Millikan

    Millikan discovered the fundamental unit of the electric charge and used a oil drop experiment. using single drops. determined not only the charge of an electron ( timeline of the atom.para. 20).

  • Niels Bohr

    Bohr Elaborated Rutherfords Idea. Bohr had created a new model of the atom to take account of atomic stababilty, orbit of the e- cannot be anywhere but quantified. Bohr had contibuted that electrons can occupy only orbits, orbits that are closer to the nucleus are more statable, at ,ower energy levels, and electrons can move from one orbit to another but absorbing or emitting energy, giving rise to characteristic spactra (timline of the atom. para 24).

  • Louis De Broglie

    De Broglie was influenced by x-rays his brother worked with. He created the theory of particles - wave duality. De Broglie believed that electrons created a dual nature, with properties representatvie of both particles and waves. ( timeline of the atom para 25).

  • James Chadwick

    updated much of Burgeoning human understanding of the atoms structure. He discovered the neutron.this became known as the 3rd basic component of the atom which was capable of increasing an atoms mass while providing no electrical charge ( timeline of the atom.para 27)

  • Glenn Seaborg

    Seaborg discovered the transurancium elemets and was responsible for the identification of more than 100 isotops of elements throughout the periodic table with help from his colleagues ( nobelprize. para. 3).

  • Fred hoyle

    In 1946 Hoyle ame up wth the idea of the stellar nucleousynthesis that he found frm he stars. In 1949 Hoyle came up with the Big Bang theory (important scientists para. 1,7).

  • Ernest Walton

    Walton was responsable for breaking up the nucleus of the lithium atom by attackng with accelerated protons, and for identifying the products as helium nuclei (nobelprize para.3).

  • Murry Gell-Mann

    Gell-Mann found that by classifying the known particles by their electrical charge and number, they could be usefully classed in octets, or categories of eight, a system he called the eightfold way.Gell-Mann estimated the charge, number and mass of an as unobserved particle, one he named "Omega-minus. he also believed that the particles in the nucleus were smaller called quarks, they are goverended by gluons (The unifyig vision of the world.para.5-6)