History+of+the+elements+and+the+periodic+table

The periodic table is a list of all the elements in order of their atomic numbers. But when did the use of the periodic table come about? Let’s find out!
 * Periodic table **


 * 1669 -** A German merchant called Henning Brand obtained phosphorus through the distillation of urine, which is the first element to be discovered having a historical register.


 * 1766 -** Hydrogen was discovered by Henry Cavendish in England.


 * 1772 -** Daniel Rutherford removed oxygen and carbon dioxide from air and showed that residual gas would not support combustion or living organism.

**1774 -** Joseph Priestly, Carl Wilhelm Scheele isolated Oxygen in England/Sweden respectively. ** 1789 - ** First modern chemical textbook by Antoine Laurent de Lavoisier, which contained a list of elements, or substances that could not be broken down any further. This list included oxygen, nitrogen, hydrogen, phosphorus, mercury, zinc and sulfur. His list, however, also included light and caloric, which he believed to be material substances.
 * 1829 -** Johann Wolfgang Döbereiner developed 'triads', groups of 3 elements with similar properties. Lithium, sodium & potassium formed a triad (Known as Group I elements). Calcium, strontium & barium formed a triad (Known as Group II elements). Sulfur, selenium & tellurium (Known as Group VI elements). Chlorine, bromine & iodine formed a triad (Known as Group VII elements).


 * 1869 -** Dmitri Mendeleev (1834-1907) had a dream of a table with elements arranged in order of relative atomic mass. He published is Periodic table and other chemists accepted it. His table then had just 69 elements.


 * 1894 -** William Ramsay discovered a previously unknown gas in the air, which he called argon. Encouraged by this discovery, he searched for more gases and succeeded in discovering helium, neon, krypton and xenon. These 5 gases were called the noble gases because they will not react with other elements. Ramsay was awarded the Noble Prize for Chemistry in 1904 for the discovery of the noble gases.


 * 1898** - Marie Curie and her husband Pierre discovered an element with properties very similar to barium and called it radium. Marie discovered that rays emitted by radium could kill cancer cells in the body, and as awarded the Noble Prize for Chemistry in 1911.


 * Present** - As of 2012, the periodic table contains 118 confirmed chemical elements. Of these elements, 114 have been recognised by the International Union of Pure and Applied Chemistry, and 112 have been officially named. 98 of these occur naturally, of which 84 are primordial (elementary). The other 14 elements only occur in decay chains of primordial elements.

|| || History of Periodic Table in a Timeline || || || 440 BC || Democritus and Leucippus propose the idea of the atom, an indivisible particle that all matter is made of. || || 360 BC || Plato coins term ‘elements’ (stoicheia) || || 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 modern chemistry || || 1754 || Joseph Black isolated carbon dioxide, which he called "fixed air". || || 1778 || Antoine Lavoisier wrote the first extensive list of elements containing 33 elements & distinguished between metals and non-metals || || 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 || || 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 || ¡John Newlands arranged the known elements in order of atomic weights & observed similarities between some elements || || 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. || || 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) ||
 * || 330 BC || Aristotle proposes the four element theory: earth, air, fire & water ||

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 * More on the periodic table**

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The history of each elements in detail: []

**Reference**
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Chemistry Insights, "O" Level 2nd Edition