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  2. History of the periodic table - Wikipedia

    en.wikipedia.org/wiki/History_of_the_periodic_table

    This is an accepted version of this page This is the latest accepted revision, reviewed on 17 November 2024. Development of the table of chemical elements The American chemist Glenn T. Seaborg —after whom the element seaborgium is named—standing in front of a periodic table, May 19, 1950 Part of a series on the Periodic table Periodic table forms 18-column 32-column Alternative and ...

  3. History of atomic theory - Wikipedia

    en.wikipedia.org/wiki/History_of_atomic_theory

    The modern periodic table is based on atomic number, which is equivalent to the nuclear charge, a change had to wait for the discovery of the nucleus. [38]: 228 In addition, an entire row of the table was not shown because the noble gases had not been discovered when Mendeleev devised his table. [38]: 222

  4. Periodic table - Wikipedia

    en.wikipedia.org/wiki/Periodic_table

    The periodic table and law are now a central and indispensable part of modern chemistry. The periodic table continues to evolve with the progress of science. In nature, only elements up to atomic number 94 exist; [a] to go further, it was necessary to synthesize new elements in the laboratory.

  5. Discovery of chemical elements - Wikipedia

    en.wikipedia.org/wiki/Discovery_of_chemical_elements

    The chemical and industrial revolutions lead to the standardization of chemical techniques and the development of atomic theory for chemistry (23 elements) The age of classifying elements and Mendeleev's periodic table; application of spectrum analysis techniques: Boisbaudran, Bunsen, Crookes, Kirchhoff, and others "hunting emission line ...

  6. Timeline of atomic and subatomic physics - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_atomic_and...

    1871 Dmitri Mendeleyev systematically examines the periodic table and predicts the existence of gallium, scandium, and germanium; 1873 Johannes van der Waals introduces the idea of weak attractive forces between molecules; 1874 George Johnstone Stoney hypothesizes a minimum unit of electric charge. In 1891, he coins the word electron for it;

  7. Types of periodic tables - Wikipedia

    en.wikipedia.org/wiki/Types_of_periodic_tables

    McCutchon's periodic table of 1950, with two double-sided flaps attached. The top flap shows the first half of the f-block. The flap under that shows the first half of the d- block. [85] Such tables, which incorporate a folding mechanism, are relatively uncommon: 1895 — An early example is the 'Flap' Model of the periodic table by David Orme ...

  8. Timeline of chemistry - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_chemistry

    An image from John Dalton's A New System of Chemical Philosophy, the first modern explanation of atomic theory.. This timeline of chemistry lists important works, discoveries, ideas, inventions, and experiments that significantly changed humanity's understanding of the modern science known as chemistry, defined as the scientific study of the composition of matter and of its interactions.

  9. Extended periodic table - Wikipedia

    en.wikipedia.org/wiki/Extended_periodic_table

    An extended periodic table theorizes about chemical elements beyond those currently known and proven. The element with the highest atomic number known is oganesson (Z = 118), which completes the seventh period (row) in the periodic table. All elements in the eighth period and beyond thus remain purely hypothetical.