Atomic Model timeline

  • Democritus
    442 BCE

    Democritus

    Made an atomic theory about the universe. his theory was about the modern principles of the conservation of energy and the irreducibility of the matter
  • Plato
    427 BCE

    Plato

    Plato found out that Ether is another thing that belonged on the periodic table. That the sun, stars and planets are all made up of ether.
  • Aristotle
    384 BCE

    Aristotle

    He found out what the four elements are: Fire, Water, Earth, and Air
  • Robert Boyle

    Robert Boyle

    He found the relationship between volume and pressure and he called it Boyle's Law. Basically means that the more pressure there is the less volume will be there
  • The Alchemists

    The Alchemists

    They developed a theory about how all metals are made up of mercury and sulfur and how its possible to change a base metal into gold.
  • Lavoisier

    Lavoisier

    He figured out that an element of a simple substance can not be broken down. He made a theory that the formation of a chemical compound from elements.
  • John Dalton

    John Dalton

    He came up with the theory that matter is composed up of different weights. They combine when the weight is a simple ratio. He also created the Billiard Ball Model.
  • Dmitri Mendeleev

    Dmitri Mendeleev

    He founded the first periodic table. That made great contributions to the atom. Out of the periodic table he created he said that there were more that still needed to be discovered.
  • The Curies

    The Curies

    He and his wife came up with the theory that radioactive materials can cause atoms to break down and then they release radiation as energy and particles.
  • J.J. Thomson

    J.J. Thomson

    He came up with the theory that energy is radiated in small units and they can be called quanta. He created the plum pudding model. He thought that the atom had a fluid in it that was positively charged with electros that were negatively charged and were floating in the liquid. He had discovered this by using a cathode ray tube.
  • Albert Einstein

    Albert Einstein

    He was known for his theories of relativity. He came up with the particle nature of light.
  • Robert Millikan

    Robert Millikan

    He came up with how o deal with the fundamentals of the universe and how the forces can exert one another, and how they can become forces.
  • Ernest Rutherford

    Ernest Rutherford

    He envisioned an atom to look like a miniature solar system. The electrons circling around the nucleus which was mostly empty space.
  • Neils Bohr

    Neils Bohr

    He made a model where the electron was only moving around the nucleus in certain orbits. It used the quantum theory. He used it to explain hydrogen.
  • Henry G. J. Mosely

    Henry G. J. Mosely

    He was an English physicist and he demonstrated that major properties of an element are determined by the atomic number. The atomic weight is not as important.
  • Werner Heisenberg

    Werner Heisenberg

    He discovered that the state of one single particle cannot be known. By state he means position and momentum.
  • Erwin Schrodinger

    Erwin Schrodinger

    He was an Austrian physicist and he came up with this thing called the electron cloud model. The cloud part is showing where an electron will be found.