History of the atom

By ac20212240
  • 400 BCE

    Democritus

    Democritus proposed that everything was made of invisible particles he called atomos which could not be divided
  • Period: 400 BCE to

    History of the atom

    By Steven Nesfeder
  • 1400

    Alchemists

    Created the most basic form of the Periodic Table by theorizing that elements were made of earth, wind, fire, and water and succeeded in obtaining some elements

  • Columb

    Stated that opposite charges attracted each other and similar charges repelled eachother

  • Lavioser

    Lavioser proposed the law of conservation of mass and proved that matter could not be created or destroyed

  • Dalton

    Proposed the law of multiple proportions

  • Mendeleev

    Organized elements by atomic mass (creating a fleshed out basis for the modern Periodic Table) and correctly predicted elements not yet discovered

  • Crookes

    Concluded that cathode rays are negatively charged

  • Marie and Pierre Curie

    Studied radioactive elements and discovered that atoms break down and release radiation when exposed to radioactive materials

  • Max Planck

    Proposed the quantum theory of energy

  • JJ Thomson

    Created a "plum pudding" atomic model

  • Einstein

    Created the Special Theory of Relativity

  • Millikan

    Discovered the quantity of charge in an electron

  • Rutherford

    Proved that atoms have a very small but extremely dense center, or nucleus

  • Bohr

    Created the planetary atomic model

  • Heisenberg

    Created the uncertainty principle and quantum mechanics theory

  • Schrodinger

    Published the probability function and created the electron cloud atomic model

  • Chadwick

    Stated that the nucleus of an atom is made of protons and neutrons and electrons orbit the nucleus. He also stated that neutrons have no charge and have the same mass as protons.