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Democritus proposed that everything is made up of indestructible components called atoms.
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Isaac Newton discovered that it was gravity that caused things to fall.
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John Dalton proposed, all elements consist of atoms that were identical and had the same mass. He also discovered that compounds were different elements atoms combined together.
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Michael Faraday developed both the laws of electrochemistry.
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Julius Plücker, built one of the first gas discharge tubes known as the cathode-ray tube.
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Dmitri Mendeleev created the periodic table.
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James Clerk Maxwell made a connection between electromagnetic and light waves and proposed the theory of electromagnetism.
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George Johnstone Stoney proposed that electricity was made up of negative particles called electrons.
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Sir William Crookes demonstrates that cathode-rays have a negative charge.
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Eugen Goldstein discovers canal rays.
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Wilhelm Roentgen discovers x-rays.
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Henri Becquerel discovers radiation.
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Ernest Rutherford discovers alpha, beta and gamma rays in radiation.
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Marie Curie discovers radium and polonium.
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Frederick Soddy invented the term ‘isotope’ to describe the unintentional breakdown of radioactive elements.
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Max Planck suggested the idea of quantization to explain how a hot, glowing object emitted light.
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Richard Abegg discovers that inert gases have a ‘stable electron configuration.
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Hans Geiger invents a machine that can detect alpha particles.
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Henry Moseley discovers that the number of protons present in an element determine said elements atomic number.
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Niels Bohr proposed that the outer orbit of an atom could hold more electrons than the inner orbit.
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Louis de Broglie discovered that electrons have a wave/particle duality.
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John Cockcroft & Ernest Walton created the first nuclear reaction.
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Paul Dirac proposed the existence of anti-particles.
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James Chadwick discovers neutrons.
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Lise Meitner, Otto Hahn & Fritz Strassmann discovered nuclear fission.
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Glenn Seaborg discovers eight transuranium elements.
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Enrico Fermi creates first man-made nuclear reactor.
