Periodic table

By f-filip
  • Period: 300 to


  • 330

    Aristotle proposes the four element theory: earth, air, fire & water

  • 440

    440 BC Democritus and Leucippus propose the idea of the atom, an indivisible particle that all matter is made of.

    440 BC Democritus and Leucippus propose the idea of the atom, an indivisible particle that all matter is made of.
  • 1605 Sir Francis Bacon published "The Proficience and Advancement of Learning" which contained a description of what would later be known as the scientific method.

  • 1661 Robert Boyle published "The Sceptical Chymist" which was a treatise on the distinction between chemistry and alchemy. It also contained some of the earliest ideas of atoms, molecules, and chemical reaction marking the beginning of the history of mode

  • 1754 Joseph Black isolated carbon dioxide, which he called "fixed air".

  • 1766 Henry Cavendish discovered hydrogen as a colorless, odourless gas that burns and can form an explosive mixture with air

  • 1773–1774 Carl Wilhelm Scheele and Joseph Priestly independently isolated oxygen

  • 1778 Antoine Lavoisier wrote the first extensive list of elements containing 33 elements & distinguished between metals and non-metals

  • 1803 John Dalton proposed "Dalton's Law" describing the relationship between the components in a mixture of gases.

  • 1828 Jakob Berzelius developed a table of atomic weights & introduced letters to symbolize elements

  • 1828 Johann Dobereiner developed groups of 3 elements with similar properties

  • 1864 Lothar Meyer develops an early version of the periodic table, with 28 elements organized by valence

  • 1864 ¡Dmitri Mendeleev produced a table based on atomic weights but arranged 'periodically' with elements with similar properties under each other. His Periodic Table included the 66 known elements organized by atomic weights.

  • 1864 ¡John Newlands arranged the known elements in order of atomic weights & observed similarities between some elements

  • 1894 William Ramsay discovered the Noble Gases.

  • 1898 Marie and Pierre Curie isolated radium and polonium from pitchblende.

  • 1900 Ernest Rutherford discovered the source of radioactivity as decaying atoms

  • 1913 Henry Moseley determined the atomic number of each of the elements and modified the 'Periodic Law'.

  • 1940 Edwin McMillan and Philip H. Abelson identify neptunium, the lightest and first synthesized transuranium element, found in the products of uranium fission.

  • 1940 Glenn Seaborg synthesised transuranic elements (the elements after uranium in the periodic table)