Periodictable

History of the Periodic Table

By pee722
  • "The Sceptical Chymist"

    Robert Boyle published this, making distinction from alchemy and chemistry. This also contained theory behind early ideas of the fundamentals of chemistry including atom, molecule and chemical reaction.
  • Phosphorus is discovered

    Discovered by German alchemist Hennig Brand
  • Hydrogen Discovery

    Henry Cavenish recognised properties of the element Hydrogen as a colorless, odourless gas that burns and is reactive with air.
  • First element list

    Antoine Lavoisier wrote a list of 33 elements, dfferentiating between metals and non-metals.
  • Dalton's Law

    John Dalton proposed "Dalton's Law", describing the relationship between different components in mixtures of gases. This helped future scientists to isolate gases and mixtures of gases in order for specific study.
  • Atomic Weights & Element Symbols

    Jakob Berzelius developed a table of atomic weights, also introducing symbols for elements.
  • Element Grouping

    Johann Dobereiner grouped elements together in 3 groups based on their properties.
  • Early Periodic Table

    Lothar Meyer organised a table of 28 elements organized by valence.
  • Development of Periodic Table

    Dmitri Mendeleev developed a table based on atomic weights, but arranged them periodically (columns) with elements sharing properties under eachother. This table included 66 elements.
  • Noble Gases

    William Ramsay discovered the Noble Gases.
  • Electrons

    Physicist J.J. Thompson discovered electrons, small negatively charged particles in an atom.
  • Development in Electrons

    John Townsend and Robert Millikan determined the exact mass and charge of electrons.
  • Discovery of Radiation

    Ernest Rutherford discovered that radioactivity was produced by decaying atoms.
  • Atomic Structure

    Ernest Rutherford and Hans Geiger discover that electrons orbit the nucleus of an atom.
  • Redefining the Periodic Law

    Henry Moseley determined the atomic number of every element, modifying the Periodic Law.
  • Synthesized Elements

    Edwin McMillan and Philip H. Abelson created neptunium for the first time, the lightest element found in uranium fission.
  • Period: to

    University of California

    In this period of time, many elements were discovered at the University of California, Berkeley. These include Plutonium, Curium, Californium, Einsteinium and Fermium.