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Calcium is the first (lightest) element to have six naturally occurring isotopes. ... about half of the world's extracted calcium is used by the United States, with ...
The chemical elements were discovered in identified minerals and with the help of the ... first refinements ... (1807), potassium (1807), calcium (1808 ...
Sodium was first isolated by Davy in the same year by passing an electric current through molten sodium hydroxide (NaOH). When Davy heard that Berzelius and Pontin prepared calcium amalgam by electrolyzing lime in mercury, he tried it himself. Davy was successful, and discovered calcium in 1808 by electrolyzing a mixture of lime and mercuric oxide.
The two discovered a new element in a molybdenum sample that was used in a cyclotron, the first element to be discovered by synthesis. It had been predicted by Mendeleev in 1871 as eka-manganese. [171] [172] [173] In 1952, Paul W. Merrill found its spectral lines in S-type red giants. [174]
Davy discovered potassium in 1807, deriving it from caustic potash (KOH). Before the 19th century, no distinction had been made between potassium and sodium. Potassium was the first metal that was isolated by electrolysis. Davy isolated sodium in the same year by passing an electric current through molten sodium hydroxide. [27]
700 BC: Pell's equations are first studied by Baudhayana in India, the first diophantine equations known to be studied. [19] 700 BC: Grammar is first studied in India (note that Sanskrit Vyākaraṇa predates Pāṇini). [20] 600 BC: Thales of Miletus is credited with proving Thales's theorem. [21] [22] [23]
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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.