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It was first identified by its characteristic emission lines in the Sun's spectrum. Lithium (Li) 3 λίθος (lithos) Greek "stone" From Greek λίθος (lithos) meaning "stone", because it was discovered from a mineral while other common alkali metals (sodium and potassium) were discovered from plant tissue. Beryllium (Be) 4
Potassium metal was first isolated in 1807 by Humphry Davy, who derived it by electrolysis of molten caustic potash (KOH) with the newly discovered voltaic pile. Potassium was the first metal that was isolated by electrolysis. [45]
Perey discovered it as a decay product of 227 Ac. [178] Francium was the last element to be discovered in nature, rather than synthesized in the lab, although four of the "synthetic" elements that were discovered later (plutonium, neptunium, astatine, and promethium) were eventually found in trace amounts in nature as well. [179]
Plumbago – a mineral, graphite; not discovered in pure form until 1564; Powder of Algaroth – antimony oxychloride, formed by precipitation when a solution of butter of antimony and spirit of salt is poured into water. Purple of Cassius – formed by precipitating a mixture of gold, stannous and stannic chlorides, with alkali. Used for glass ...
A lilac flame was observed, the result of successfully breaking down potash into its constituent elements – one of which, was the previously never before seen element potassium. Davy went on to add six new elements to Lavoisier's list, as well as confirming that substances like chlorine and iodine were also elements.
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.
A 100,000-year-old ochre-processing workshop was found at Blombos Cave in South Africa. It indicates that early humans had an elementary knowledge of mineral processing. Paintings drawn by early humans consisting of early humans mixing animal blood with other liquids found on cave walls also indicate a small knowledge of chemistry. [3] [4]
Aristarchus of Samos (/ ˌ æ r ə ˈ s t ɑːr k ə s /; Ancient Greek: Ἀρίσταρχος ὁ Σάμιος, Aristarkhos ho Samios; c. 310 – c. 230 BC) was an ancient Greek astronomer and mathematician who presented the first known heliocentric model that placed the Sun at the center of the universe, with the Earth revolving around the Sun once a year and rotating about its axis once a day.