Rutherford atom

The Atom

By Nbeam
  • 450 BCE

    No Atoms

    Aristotle didn't come up with the idea of the atom but, he did think that all the things on Earth were made out of elements. Elements of water, earth, fire, and air.
  • 400 BCE

    The Atom

    In 400 B.C., Democritus came up with the concept of the atom. The theory that Democritus came up was was that everything in the universe was made out of atoms, which were described as microscopic and indestructible.
  • 400

    Alchemistry

    Alchemy was the idea of morphing base metals (lead, copper, zinc, etc.) into noble metals (gold).

  • Boyle's Law

    Robert Boyle came up with, Boyle's Law, in 1688. Boyle's Law said that the volume of gas at a constant temperature depends on the amount of pressure that gets applied to it.

  • John Dalton

    John Dalton
    John Dalton was the first to create a chart of atomic weights.

  • Mendeleev

    Mendeleev
    Dmitri Mendeleev was the one who predicted the existence and properties of new chemical elements. For this, Mendeleev gets most of the credit for the creation of the periodic table.

  • Subatomic Particles

    Subatomic Particles
    J.J. Thomson was experimenting with Crookes and then discovered that all atoms have a slight negative charge to it, leading to the discovery of the electron. He also discovered isotopes for stable elements. This is a picture of Thomson's, Plum Pudding Model and how he thought the atom looked like.

  • Proton and Nucleus Discovered

    Because of an experiment that Hans Geiger did, he noticed that when he shot a beam of alpha particles at a thin sheet of gold, occasionally the light would bounce off of something instead of going through the gold. This meant that the positively charged alpha particles were hitting something else that is positive meaning that the atom had to have a slight positive charge to it. This is how Hans Geiger learned about protons.

  • Charge of an Electron

    Charge of an Electron
    Robert Millikan did an experiment called, the oil drop experiment. The oil drop experiment helped him to learn the charge of an electron. This is a picture of what the oil drop experiment looked like.

  • The Rutherford Model

    The Rutherford Model
    Ernest Rutherford came up with the Rutherford Model. The Rutherford Model showed that the atom had a nucleus that a had small charge. The nucleus was surrounded by empty space with tiny electrons circling it. This is an example of the Rutherford Model.

  • The Bohr Model

    The Bohr Model
    In 1913, Niels Bohr which showed that the atom has a small, positively charged nucleus and is surrounded by electrons. Bohr also had a theory about the Hydrogen Atom.

  • Neutrons

    James Chadwick noticed that there was a neutral electrical charge that was about the same size as the proton. Later, he called this neutrally charged particle, the neutron.