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Alchemists believed that everything was made up of four elements, which were earth, air, fire, and water. This laid the foundation for the modern Periodic Table of Elements.
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Democritus theorized that all matter was made of small indivisible particles. Democritus did not believe in any gods, unlike many other people at the time.
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Plato theorized that the heavens and objects in the heavens were made of an element called ether. Plato also made significant contributions to philosophy.
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Robert Boyle defined an element as a substance that cannot be broken down into more substances. Robert Boyle also researched alchemy.
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Antoine Lavoisier came up with the Law of Conservation of Mass, which states that matter cannot be created or destroyed, only changed. Antoine Lavoisier also gave oxygen its name.
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John Dalton used experiments to prove that atoms exist. John Dalton also researched color blindness.
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The Billiard Ball Model of the atom was one solid particle. There were no subatomic particles.
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Amedeo Avogadro proposed that the atoms of elemental gases can be joined together in molecules instead of existing as individual atoms. Amedeo Avogadro was a lawyer before he became a scientist.
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Dmitri Mendeleev created the first periodic table. Dmitri Mendeleev also discovered the Periodic Law.
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J.J. Thomson discovered the electron. J.J. Thomson also proposed the Plum Pudding Model of the atom.
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Pierre and Marie Curie discovered the radioactive elements polonium and radium. Marie Curie is the only person to have won a Nobel Prize in both physics and chemistry.
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The Plum Pudding Model of the atom was made up of many electrons surrounded by positively charged matter. The Plum Pudding Model did not have a nucleus.
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Albert Einstein mathematically proved that atoms exist. Einstein also helped develop the atomic bomb.
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Robert Millikan discovered the charge of an electron. Robert Millikan also created anti-submarine technology for the U.S.A. during WWI.
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Ernest Rutherford discovered that atoms were made up of a nucleus that is surrounded by electrons. Ernest Rutherford is often referred to as the Father of Nuclear Physics.
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Niels Bohr discovered that electrons orbit around the nucleus of an atom. Niels Bohr also researched quantum mechanics.
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Henry G.J. Moseley found the atomic number of each element using x-rays. Henry G.J. Moseley was killed during WWI at the age of 27.
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The Solar System Model of the atom has a nucleus made up of protons and neutrons that is orbited by electrons. The electrons move in set paths around the nucleus.
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Erwin Schrodinger created an equation to predict the positions of a particle at a certain time. Erwin Schrodinger also developed the Electron Cloud Model of the atom.
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The Electron Cloud Model of the atom has a nucleus made up of protons and neutrons that is orbited by electrons. The electrons do not move in set paths around the nucleus.
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Werner Heisenberg discovered the Uncertainty Principle, which states that the position and momentum of a particle cannot both be known exactly. Heisenberg was awarded the Nobel Prize in Physics in 1932.
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James Chadwick discovered the neutron. James Chadwick was awarded the Nobel Prize for his discovery of the neutron.
