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Period: 460 to 370
Democritus
Atoms are in uniform, solid, hard, incompressible, indestructible, and they moved in infinite numbers through empty stance until stopped -
John Dalton
All matter is comprised of indivisible and indestructible atoms with distinct masses and properties. He also inferred that gases must consist of tiny moving particles. -
Antoine Lavoisier
Water is not an element, but is a compound of oxygen and inflammable air -
Period: to
Max Planck
Originated the quantum theory, deduced the relationship between the nervy and frequency of radiation. -
Marie Curie
Radioactivity doesn’t depend on how atoms are arranged, but instead it originates within the atoms themselves -
Period: to
Robert Millikan
Proved all electrons have a constant quantity, demonstrating the atomic structure of electricity. Discovered an accurate determination of the charge carried by an electron. -
Period: to
Ernest Rutherford
Atoms contain a positively charged nucleus much smaller than the actual atom -
Period: to
Erwin schrodinger
made a wave equation that accurately calculated the energy levels of electrons in atoms. He also used math to find out where electrons were and how frequently they appeared. -
Period: to
James Chadwick
Proved the existence of neutrons. Also Interpreted radiation as being made of particles of mass equal to that of the proton but without electrical charge. -
Period: to
Louis De Brogile
Introduced the idea of particles such as electrons, being described as waves. -
J.J Thompson
All matter contains particles of the same kind -
Period: to
Werner Heisenberg
Formulated a type of quantum mechanics based on matrices -
Albert Einstein
Mathematically proved the existence of atoms, helping revolutionize all sciences through statistics and probability. -
Niels Bohr
Proposed that some physical quantities only take discrete values, but only in perscribed orbits. He also concluded that the nucleus of an atom is similar to a drop of water.