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330
Four element theory is produced and recorded (330 BC)
Greek philosopher Aristotle lists four known element at the time earth, air, fire & water." From this he purposed the four element theory. -
440
The idea of the atom (440BC)
Greek philosopher "Democritus" propose the first ever idea of the existence of the indivisible particle "atoms". -
500
Mercury is discovered (500BC)
The earlist known report of the discovery of Mercury is dated back to around 500BC-510BC -
Phosphorus is discovered
By German alchemist Hennig Brand. Found by boiling, filtering and otherwise processing as many as 60 buckets of urine. -
Cobalt is discovered
Cobalt is discovered by a Swedish chemist Georg Brandt. -
Platinum is discovered
Platinum is discovered by General Antonio de Ulloa -
Nickel is discovered
By the Swedish chemist Axel Fredrik Cronstedt. -
Carbon dioxide is isolated
Scottish physician Joseph Black isolated carbon dioxide in which he purposes that the isolated air is "fixed air" -
Magnesium is discovered
Discovered by Joseph Black in England. -
Hydrogen is discovered
By English chemist and physicist Henry Cavendish. -
Nitrogen is discovered
By Scottish chemist Daniel Rutherford. -
Chlorine is discovered
By a Swedish scientist, Carl Willam Scheele. -
Manganese is discovered
Discovered by Swedish chemist Johann Gottlieb Gahn. -
Oxygen is discovered
Disovered by English chemist Joseph Priestley and Swedish chemist Carl Wilhelm Scheele. -
Molybdenum is discovered
Discovered by Swedish chemist, Carl Welhelm Scheele -
Tellurium is discovered
Austrian mineralogist Franz-Joseph Müller von Reichenstein discovers the element in a gold ore near Sibiu, Romania. -
Tungsten is isolated
In 1783, José and Fausto Elhuyar isolate tungsten with the reduction of wolframite acid with charcoal. -
Uranium and Zirconium are isolated and discovered
By German chemist Martin Heinrich Klaproth. -
Titanium is discovered
Discovered by English clergyman William Gregor. -
Chromium and Beryllium are isolated
Discovered by by the English chemist Charles Hatchett. -
Niobium is discovered but not isolated
Discovered by the English chemist Charles Hatchett. -
Tantalum is discovered and isolated
Swedish chemist and mineralogist Anders Gustaf Ekeberg discovers Tantalum. -
Cerium is discovered in Sweden and Germany
Found by Jakob Berzelius and Wilhelm Hisinger and Martin Heinrich Klaproth. -
First atomic theory of matter is released to the public
John Dalton proposed an "atomic theory" that discussed that atoms are indivisible and indestructible, that atoms that were in a specific element are identical in mass and properties. He also stated that compounds are formed by two or more atoms. -
Vanadium is discovered
Discovered by Mexican chemist Andrés Manuel del Río -
Palladium is discovered.
Discovered by English chemist William Hyde Wollaston, two years before English chemist Smithson Tennant discovers it. -
Iridium is discovered
Discovered by English chemist Smithson Tennant. -
Osmium is discovered
English chemist Smithson Tennant discovers Osmium. -
Potassium and Sodium are discovered, isolated and reported to the public
Discovered and isolated by English chemist Sir Humphry Davy and reported to the public by his colleagues. -
Barium, strontium and calcium are discovered and isolated.
English chemist Sir Humphry Davy discovers three more elements over the course of one year. -
Iodine is isolated and discovered
Discovered by the French chemist Bernard Courtois. -
Lithium is discovered.
Discovered by Swedish chemist Johan August Arfwedson. -
Cadmium is discovered
Discovered by German chemist Friedrich Stromeyer. Wasn't isolated till 1818. -
Selenium is discovered
Discovered by Swedish chemists Jöns Jacob Berzelius and Johan Gottlieb Gahn. -
Silicon is discovered
Discovered by Jöns Jacob Berzelius, a Swedish chemist. -
Aluminium is discovered
Discovered by Danish chemist and physicist Hans Christian Oersted. -
Bromine is discovered
C. Lowg in Germany and Antoine-Jérôme Balard in France discover Bromine. -
Thorium is isolated and discovered
Discovered and isolated by Swedish chemist Jöns Jakob Berzelius. -
Lanthanum is disocvered.
Swedish chemist, Carl Gustaf Mosander discovers Lanthanum -
Terbium and Erbium are discovered
Both discovered by Swedish chemist, Carl Gustaf Mosander. -
Ruthenium is discovered
Russian scientist Karl Ernst Claus discovers the element and isolated it the following year. -
Caesium is discovered
Discovered by German chemists, Robert Wilhelm Bunsen and Gustav Robert Kirchhoff. -
Rubidium is discovered
Discovered by German chemists Robert Bunsen and Gustav Kirchhoff. -
Thallium is discovered
Discovered by British physicist Sir William Crookes. -
The use of Atomic weights is first used to arrange discovered elements.
Geologist, A.E.Beguyer de Chancourtois presented to the French Academy of Sciences, the use of atomic weights to reveal that the elements were arranged according to their atomic weights with similar elements occurring at regular intervals. This data was presented on a table known as the ‘telluric screw’. based on tables used in geology at the time. -
Indium is discovered
Discovered by erman chemists Ferdinand Reich and Hieronymus Theodor Richter. -
Law of octaves surfaces to the public
English chemist John Newlands noticed that, if the elements were arranged in order of atomic weight, there was a periodic similarity every 8 elements. -
Known Elements are presented on the first periodic table.
In 1869, Russian chemist Dmitri Mendeleev presented to the public a periodic table based on atomic weights but arranged ‘periodically’. On this table, know elements with similar properties appeared under each other, but due to the lack of found elements; numerous gaps were left for future discoveries of elements. -
Gallium is discovered
Discovered by Paul-Émile Lecoq de Boisbaudran. -
Ytterbium is discovered
Discovered by the Swiss chemist Jean-Charles-Galissard de Marignac. -
Holmium is discovered
Discovered by Marc Delafontaine and Jacques-Louis Soret in Switzerland. -
Thulium and Scandium are discovered
Discovered by Swedish chemists; Per Theodor Cleve and Lars Fredrik Nilson. -
Samarium is discovered
Discovered by French chemist, Jean Charles Galissard de Marignac in Switzerland. -
Gadolinium is discovered
Discovered by a Swiss chemist, Jean Charles Galissard de Marignac. -
Praseodymium is discovered
Discovered by Carl F. Auer von Welsbach, a German chemist. -
Radioactivity is discovered
Discovered by French physicist Antoine Bequerel as he discovered by accident that uranium salts emitted a penetrating radiation that could be registered on a photographic plate, with this led him to futher investigation which led Antoine that this "radiation" was different and needed to be recorded. -
Noble Gases are discovered.
Discovered by Scottish chemist William Ramsay. He also discovered that these newly discovered elements needed to be put into a group of their own due to their atomic weight and unique structure. -
Cause of Radioactivity is discovered
New Zealand physicist and chemist "Ernest Rutherford" annouces that radioactivity is caused by the breakdown of atoms. -
Electrons orbit the nucleus of an atom is discovered
Discovered by New Zealand physicist and chemist "Ernest Rutherford" -
Atomic numbers are first used.
English physicist Henry Moseley, provided atomic numbers based on the number of electrons in an atom. He also stated that if currently discovered and yet to be discovered elements were to be arranged in order of their atomic number rather than the element's atomic weight, they give a better fit and structure within the ‘periodic table’. -
Protons are discovered in atomic nucleuses
New Zealand physicist and chemist "Ernest Rutherford" states that protons exist in atomic nucleuses. -
Existence of neutrons is discovered
Discovered by english physicist James Chadwick. James Chadwick purpose and recorded that they must be had been something else in a atom besides charged electrons and from this he investgated atoms in known/discovered elements to eventully discovering that near the existence of protons and electrons, neutrons existed as well. -
Transuranium elements are discovered
American scientist, Glenn Seaborg along with his colleagues discovered the elements from atomic numbers 94 to 102. Upon discovering these elements, the periodic table was changed to fit these elements. They become the the actinide series of the periodic table. -
Period: to
Four elements are discovered by Glenn Seaborg
Glenn Seaborg and his colleagues discover, Plutonium, Americium, Berkelium and Curium -
Einsteinium and Fermium are discovered
Discovered by Albert Ghiorso and his co-workers at the University of California at Berkeley.