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__**The Atom**__
The atom is the building block of matter and throughout history there has been many different models of what the atom looks like. With current technologies, It is impossible to know exactly what atoms look like. Since the current excepted model is nearly a hundred years old, the Rochester Analytical Laboratory has hired us to created a new model. To do this we research five of the major models of the past and new discoveries in the field of atomic physics.

__Timeline__

 * John Dalton (1803)** - He modernized the atomic theory. He proposed that elements consisted of atoms that were identical and had the same mass. He also stated that compounds were atoms from different elements combined together.


 * Eugen Goldstein (1886)** - He discovered canal rays which have a positive charge equal to an electron.


 * J.J Thomson (1897)** – Determined the charge to mass ratio of electrons. He discovered the electron, and that it was negatively charged. He showed this discovery through his Plum-Pudding Model, which had negatively charged particles spread throughout the atom.


 * Ernest Rutherford (1898)** – Discovered alpha, beta, and gamma rays in radiation.


 * Maxwell Planck (1900)** – proposed the idea of quantization, radiation that has energy, to explain how a hot, glowing object omitted light.


 * Albert Einstein (1905)** – proposes the quantum of light hypothesized that light was made up of different particles.


 * Robert Millikan (1909)** – Conducted the Oil Drop Experiment which determined the charge and the mass of electrons.


 * Ernest Rutherford (1909)** – Showed that the atom was made up of mostly empty space with a positively charged nucleus. This was discovered through his Gold Foil Experiment. This consisted of a series of test in which they shot positively charge helium particles into a layer of gold foil.


 * Niels Bohr (1913)** – Stated that electrons can only exist in specific energy states. He did the Planetary Model, which stated that electrons move in circular orbits within specific energy levels.


 * Werner Heisenberg (1925)** – invented matrix mechanics, the first version of quantum mechanics. This method was used to calculate the behavior of electrons and other subatomic particles.


 * Erwin Schrodinger (1930)** – introduced the term “wave mechanics” as a mathematical model of an atom. He also said that the electrons were “continuous clouds.” With this he made the Electron Cloud Model, this stated that the region around the nucleus where e- are likely to be found.


 * James Chadwick (1932)** - He identified nuclear particles with positive charges, which he called protons. He stated that there was a neutral particle with almost the same mass as the proton. This was known as the neutron.

Worked on by Caleb McLean and Tori Raderstorf