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Michael Sendivogius (/ ˌ s ɛ n d ɪ ˈ v oʊ dʒ i ə s /; Polish: Michał Sędziwój; 2 February 1566 – 1636) was a Polish alchemist, philosopher, and physician.A pioneer of chemistry, he developed ways of purifying and creating various acids, metals, and other chemicals.
Photosynthetic prokaryotic organisms that produced O 2 as a byproduct lived long before the first build-up of free oxygen in the atmosphere, [5] perhaps as early as 3.5 billion years ago. The oxygen cyanobacteria produced would have been rapidly removed from the oceans by weathering of reducing minerals, [citation needed] most notably ferrous ...
The earliest recorded metal employed by humans seems to be gold, which can be found free or "native". Small amounts of natural gold have been found in Spanish caves used during the late Paleolithic period, around 40,000 BC. [5] The earliest gold metallurgy is known from the Varna culture in Bulgaria, dating from c. 4600 BC. [6]
2 combines with atomic oxygen made by the splitting of O 2 by ultraviolet (UV) radiation. [22] Since ozone absorbs strongly in the UV region of the spectrum, the ozone layer of the upper atmosphere functions as a protective radiation shield for the planet. [22] Near the Earth's surface, it is a pollutant formed as a by-product of automobile ...
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 new analysis offers clues to the mystery of this tiny oddball’s place on the human family tree. Newly discovered fossils shed light on the origins of curious ‘hobbit’ humans Skip to main ...
The Great Oxidation Event (GOE) or Great Oxygenation Event, also called the Oxygen Catastrophe, Oxygen Revolution, Oxygen Crisis or Oxygen Holocaust, [2] was a time interval during the Earth's Paleoproterozoic era when the Earth's atmosphere and shallow seas first experienced a rise in the concentration of free oxygen. [3]
Astronomers using the Gaia space telescope have located two ancient streams of stars that helped the Milky Way galaxy grow and evolve more than 12 billion years ago.