Atomic Theory Timeline

By zekeclement2013
  • 100

    Aristotle

    Aristotle
    Aristotle was born during 384 B.C. Aristotle was known by a vast amount of people in his time and modern day. He became well known because of his ideas about science. Aristotle thought that everything was made of the 5 elements, water, fire, earth, air, and aether.
  • 100

    Democritus

    Democritus
    Democritus was born during 460 B.C. He was thought crazy by many people because of his perspective on atoms. Democritus believed that atoms were so small, they could not be seen. He also thought that there was small gaps between the atoms.
  • Period: 100 to

    Timeline

  • John Dalton

    John Dalton
    John Dalton's atomic theory is very similar to Democritus's theory. Dalton thought that compounds were formed when 2 or more different atoms were combined. He also thought that chemical reactions were the rearrangement of atoms.

  • Sir William Crookes

    Sir William Crookes
    Sir William Crookes was the first inventor of the discharge tube. This invention that he created helped him discover cathode rays. Crooke's invention was admired, and is still used today.

  • Dmitri Mendeleev

    Dmitri Mendeleev
    Dmitri Mendeleev created his own version of the periodic table. He used it to correct the properties of some elements that had already been discovered. Mendeleev also predicted the properties of elements that hadn't been discovered.

  • J.J. Thomson

    J.J. Thomson
    J.J Thomson was the first discoverer of the electron. He proved that cathode rays were actually electrically charged particles. To prove this, he conducted an experiment using Crooke's Tube.

  • Ernest Rutherford

    Ernest Rutherford
    Ernest Rutherford worked with J.J Thomson on the effect that X-rays had on gasses. This led them to the discovery of the electron particle.

  • Niels Bohr

    Niels Bohr
    Niels Bohr created an atomic model known as the Bohr Model. In this model, an atom is a small positively charged nucleus in which electrons travel in a circular orbit around it.

  • Erwin Schrödinger

    Erwin Schrödinger
    Erwin Schrödinger used mathematical equations to find the probability of finding an electron in a specific position. He portrayed an atom as a nucleus surrounded by an electron cloud.

  • James Chadwick

    James Chadwick
    James Chadwick was well-known, and won an award for his discovery of the neutron. During World War II, he helped create a nuclear bomb for the U.S.