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*Note: Year is in BCE.
Theorized that everything was made of "atoms," little particles of matter that are and always were in motion and indestructible. Little did the cheeky swankswinger know that we would come to break those indestructible nanobehemoths. -
Sir Isaac Newton proposed a mechanical universe with small solid masses in motion.
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John Dalton came up with the idea of the "atomic theory," in which spherical, solid atoms are based on measurable attributes of mass.
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Mendeleev grouped elements into 7 groups, categorizing them based on similar properties. He also created the Periodic Law (properties of elements are periodic functions of their atomic weights).
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Discovered the electron and found the charge:mass ratio of the electron.
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Studied radioactivity in uranium/thorium. Along with her husband, discovered polonium & radium.
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Conducted the oil drop experiment to determine the charge and mass of an electron.
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Rutherford was the first person to deliberately transmute one element to another. While working with Niels Bohr, he came up with the idea of neutrons existing as parts of atoms.
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Discovered that heavier elements trap neutrons and create unstable byproducts that go through nuclear fission.
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Along with Meitner, did experiments indicating that heavy elements capture neutrons, resulting in fission.
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Applied quantum theory to the atomic structure, stating that electrons travel in stationary orbits, which are defined by their angular momentum.
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Measured the wavelengths of x-rays, ultimately determining that the Periodic Law should not be based mostly upon atomic weight.
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First to discover the neutron, even though this discovery was predicted by Ettore Majorana. Chadwick's discovery played a large role in the ability to produce heavier elements than was previously possible, as well as coming to understand much of nuclear fission.
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Heisenberg created the Uncertainty Principle, which states that the exact location and energy of an electron can not be measured at the same time.
