Atomic Theory

By MurphyA06
  • 600 BCE

    Thales

    Had the idea that everything is made of atoms, but Democritis added that the smallest particle can't be destroyed.
  • 546 BCE

    Thales

    created the atomic theory that states that all matter is composed of particles called atoms, based on Democritus
  • 430 BCE

    Democritus

    Demcritus had the idea that you couldn't cut things infinitely, but it ended at an indestructible thing, which he named Atoms, later to be known as Atoms.
  • 380 BCE

    Aristotle

    Thought that all materials on Earth were made of the four elements, earth, fire, water and air. He believed all substances were made of small amounts of these four elements.

  • Isaac Newton

    Newton suggested that atoms are held together with attractions, otherwise known as forces. He also stated that "matter is formed of solid, massy impenetrable particles”.

  • John Dalton

    Law of Multiple Proportions, proposed first Atomic Theory:
    1- all matter is made up of tiny indivisible atoms
    2- atoms of the same element are the same
    3- atoms of different elements are different
    4- atoms combine in whole number ratios to form compounds Creator of the "Dalton Atomic Model", or "Dalton's Model".

  • Michael Faraday

    Discovered electromagnetic induction.

  • William Crookes

    Discovery of the element thallium and for his cathode-ray studies, fundamental in the development of atomic physics

  • Dmitri Mandaleev

    Created the 63 element periodic table

  • G.J. Stoney

    Discovered electrons as the fundamental unit quantity of electricity.

  • E. Goldstein

    Discovered and rays and protons.

  • J.J. Thomson

    Led to the discovery of electrons and invented the Plum Pudding Model and found protons in cathode ray tubes.

  • Max Planck

    Discovered the Quantum Theory

  • Hantaro Nagaoka

    Created the quasi-planetary model of the atom.

  • Albert Einstein

    Discovered the Photoelectronic Effect

  • Rutherford

    Rutherford conducted his "Gold Foil" experiment and created the Rutherford Atom model

  • Richard Abegg

    Created Abegg's rule and the theory of freezing-point depression.

  • H.G.J. Moseley

    Moseley used equipment he made to prove that every element’s identity is determined by the number of protons it has.

  • Frederick Soddy

    Studied radiation until his wife died.

  • Francis William

    Discovered a large amount of isotopes.

  • Niels Bohr

    Created the Bohrs Model.

  • Louis De Broglie

    Introduced the idea that all matter has wave forms.

  • Mary Sklodowska Curie

    Discovered x-rays after her husband, Pierre Curie, died.