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Oxygen evolution is the chemical process of generating elemental diatomic oxygen (O 2) by a chemical reaction, usually from water, the most abundant oxide compound in the universe. Oxygen evolution on Earth is effected by biotic oxygenic photosynthesis , photodissociation , hydroelectrolysis , and thermal decomposition of various oxides and ...
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 ...
Aluminium (or aluminum) metal is very rare in native form, and the process to refine it from ores is complex, so for most of human history it was unknown. However, the compound alum has been known since the 5th century BCE and was used extensively by the ancients for dyeing .
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.
The Great Oxidation Event (GOE) or Great Oxygenation Event, also called the Oxygen Catastrophe, Oxygen Revolution, or Oxygen Crisis, 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. [2]
In addition, he discovered a process similar to pasteurization, [20] along with a means of mass-producing phosphorus (1769), leading Sweden to become one of the world's leading producers of matches. Chlorine gas. Scheele made one other very important scientific discovery in 1774, arguably more revolutionary than his isolation of oxygen.
The earliest gold artifacts were discovered at the site of Wadi Qana in the Levant. [13] Silver is estimated to have been discovered in Asia Minor shortly after copper and gold. [14] There is evidence that iron was known from before 5000 BC. [15] The oldest known iron objects used by humans are some beads of meteoric iron, made in Egypt in ...
Earliest humans Charcoal and soot were known to the earliest humans, with the oldest known charcoal paintings dating to about 28000 years ago, e.g. Gabarnmung in Australia. [1] [2] The earliest known industrial use of charcoal was for the reduction of copper, zinc, and tin ores in the manufacture of bronze, by the Egyptians and Sumerians. [3]