Atomic Timeline

  • 440


    Democritus was born in Greece, 460 b.c. Democritus was a Philospher who came up with the idea of the atom in 440 b.c. Some of the major contributions Democritus made to the atomic theory is that matter is made up of indivisible atoms, atoms are indestructible, there are an endless amount of atoms, etc.
  • John Dalton's atomic theory

    John Dalton's atomic theory
    John Dalton was born in England, 1766. He was a british chemicist, physicist, and meteorologist. John Dalton added to the atomic theory the ideas that all substances are made of atoms, atoms join with other atoms to make new substances, atoms of the same element are alike and atoms of different elements are different, etc.
  • Thompson's Atomic Theory

    Thompson's Atomic Theory
    Sir Joseph John Thompson was born in England, 1856. Thompson was a british physicist. Some major contributions Thompson made to the atomic theory was that he discovered electrons, he discovered isotopes, and he was a role model to his assistants and son because they later also won nobel prizes.
  • Rutherford's Atomic Theory

    Rutherford's Atomic Theory
    Ernest Rutherford was born New Zealand, 1871. He was a british physicist who is now known as the father of nuclear physics.SOme of the major contributions he made to the atomic theory are that he discovered the concept "half-life", the discovery of proton, and created the Rutherford model.
  • Bohr's Atomic Theory

    Bohr's Atomic Theory
    Niels Bohr was born in Denmark, 1885. He was a Danish physicist and philosopher. Some of the major contributions he made to the atomic theory are that he helped understand atomic structure, he helped understand quantum theory, he developed the Bohr model, etc.
  • Modern Atomic Theory

    Modern Atomic Theory
    The modern atomic theory is a scientific theory that states that matter is composed of discrete units called atoms, as opposed to the concept which held that matter could be divided into any small quantity.