• 450


    Democritus came up with the theory that anything and everything is made up of extremely small unreducilble particles called Atoms, in 400 B.C.
  • 450


    Aristotle came up with the original Scientific Method containing four causes/ questions involved in the whole process. The categories of this original method were single words compared to propositions. They included the following 10, substance, quantity, quality, relation, place, time, situation, condition, action, passion. They would be arranged simply in the order of the way that you would ask each question. He came up with this method near 350 B.C.
  • Period: 450 to

    Scientists of the Past

  • Antoine lavoisier

    Antoine lavoisier
    In 1777 he demonstrated the Conservation Of Matter( that being, Matter cannot be created nor can it be destroyed), in a chemical reaction.Then used this to help him state the difference between an element and a compound.
  • Joseph Proust

    Joseph Proust
    he experimented to show a compound and always came up with the same ratio.this was called the law of constant composition
  • John Dalton

    John Dalton
    John Dalton modernized the atomic theory in 1803. His model showed that all atoms in any given chemical is the same as another atom in that same chemical. The model also helped him show that the atoms of different elements are different from one another judging by their atomic weight.
  • J.J. Thomson

    J.J. Thomson
    In 1898, he discovered the electron, that being the part of an element being negatively charged. He showed his discovery through a model, The Plum-Pudding Model, which had negatively charged particle spread out evenly throughtout a circle of evenly charged material.
  • Robert Millikan

    Robert Millikan
    His earliest major success was the accurate determination of the charge carried by an electron, using the elegant "falling-drop method"; he also proved that this quantity was a constant for all electrons (1910), this led to his discovery of the atomic structure of electricity.
  • Ernest Rutherford

    Ernest Rutherford
    In 1909 he showed that the atom is made up mostly of empty space with a small positively charged nucleus containing most of the mass and low mass negatively charged particles. He went on to experimentally identify nuclear particles with positive charges, that he went on to name as Protons. From his identification of the proton, he stated that there was a neutral particle with nearly the same mass as a proton, this particle became known as the Neutron.
  • Niels Bohr

    Niels Bohr
    In 1913 he developed the first successful model of the atom, since then we still use Bohr's model to explain the many aspects of physical occuring such as the appearance of spectra. He helped fix a problem involving why the electron particles dont just fall down towwards the middle of the nucleus. He came up with the reason being that the electrons are confined to a specific orbit that were quantized, so even with the loss of energy the electrons stay in their orbit.