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Democritus
Democritus was born in Adbera, Greece. His name is mostly associated with the foundlings of the atomic theory of matter, stating that all matter is composed of single indivisible atoms. -
Law of Conservation of Mass
Established by French chemist Antoine Lavoisier. It states that mass is neither created nor destroyed in any ordinary chemical reaction. -
John Dalton
Born September 6th,1766, in Eaglesfield,Cumbria,UK. Known for Dalton's Atomic Theory. -
Dalton's Atomic Theory
Dalton's theory was based on the premise that the atoms of different elements could be distinguished by differences in their weights. -
Ernest Rutherford
Born August 30,1871 in Brightwater, New Zealand. Known as the father Nuclear Physics. -
Albert Einstein
Einstein was born on March 14, 1879 in Ulm, Germany. Best known for his mass–energy equivalence formula E = mc2 -
Niels Bohr
Bohr was born October 7,1885 in Copenhagen, Denmark. He is the father of Quantum Theory. He proposed that the atom "is successive or bital shells of electrons.Bohr came up with the Bohr model of the atom with the atomic nucleus at the centre and electrons in orbit around it, which he compared it to the planets orbiting the Sun -
Erwin Schrodinger
Schrodinger was born on August 12, 1887 in Vienna,Austria. Known for developing a number of fundamental results in the field of quantum theory, which formed the basis of wave mechanics. -
Henry Moseley
In 1913, English physicist Henry Moseley observed the properties of x-rays from about a dozen consecutive elements in the periodic table. In doing so, he discovered that the wavelength of the x-rays became shorter as the atomic weight increased. -
Cathode Ray Tube
In 1897,cathode rays were composed of a unknown negatively charged particle, and is credited with the discovery of the electron.
Created by: J.J Thomson -
Plum Pudding Atomic Model
The plum pudding model of the atom was propsed in 1904, before the discovery of the atomic nucleus in order to add the electron to the atomic model. -
Gold Foil Experiment
This was an experiment to prove the structure of an atom,but because of the unexpected results of the experiment demonstrated for the first time the existence of the atomic nucleus, leaded to the downfall of the plum pudding model of the atom, and the development of the Rutherford model.
It was performed by hans Geiger and Ernest Marsden but directed by Ernest Rutherford -
Rutherford Model
Rutherford directed the famous Geiger-Marsden experiment in 1909 which suggested, upon Rutherford's 1911 analysis, that the so-called "plum pudding model" of J. J. Thomson of the atom was incorrect.The surprising results of this experiment demonstrated the existence of the atomic nucleus and became an integral part of the Rutherford model of the atom. -
Bohr Planetary Model
This model portrays the atom as small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus
Launched by Niels Bohr -
Robert Millikan
Born March 22, 1868 in Morrison, Illinois. Mostly known for his measurement of the elementary electronic charge and for his work on the photoelectric effect in 1923. -
Quantum Mechanical Model
In 1926, Schrödinger was able to formulate an equation that helped to clear up the confusion that Heisenberg had caused by telling the world we can’t determine what the atom really looks like. It is by using Schrödinger’s equation that we are able to diagram the electron clouds, or orbitals, where we will most likely find the electron at any point in time. -
Heisenberg's Uncertainty Principle
Werner Heisenberg stumbled on a secret of the universe: No thing has a definite position, a definite trajectory, or a definite momentum, but Albert Einstein was able to explain this theory as many others could not. -
James Chadwick
james Chadwick was born on October 20, 1891 in Bollington, Cheshire,UK. In 1932, Chadwick proved the existance of neutron. He discoverd a particle within the nucleus that has a mass similar to that of a proton. -
J.J Thompson
Born December 18,1856 in Manchester,UK.
