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[[File:lighterstill.jpg]][[File:Newcatalyst.jpg|right|frame]]
[[File:lighterstill.jpg]][[File:Newcatalyst.jpg|right|frame]]
*[http://en.wikipedia.org/wiki/1902 1902]
==Definitions==
*1: a substance that enables a [[chemical]] [[reaction]] to proceed at a usually faster [[rate]] or under different conditions (as at a lower [[temperature]]) than otherwise possible
*2: an agent that provokes or speeds significant [[change]] or [[action]]
==Description==
'''Catalyst''' (or Catalysis) the [[process]] in which the rate of a [[chemical]] [[reaction]] is either increased or decreased by means of a chemical substance known as a catalyst. Unlike other reagents that [[participate]] in the chemical reaction, a catalyst is not consumed by the reaction itself. The catalyst may participate in multiple chemical [[transformations]]. Catalysts that speed the reaction are called positive catalysts. Catalysts that slow down the reaction are called negative catalysts or inhibitors. Substances that increase the [[activity]] of catalysts are called promoters and substances that deactivate catalysts are called catalytic [[poison]]s.
'''Catalyst''' (or Catalysis) the [[process]] in which the rate of a [[chemical]] [[reaction]] is either increased or decreased by means of a chemical substance known as a catalyst. Unlike other reagents that [[participate]] in the chemical reaction, a catalyst is not consumed by the reaction itself. The catalyst may participate in multiple chemical [[transformations]]. Catalysts that speed the reaction are called positive catalysts. Catalysts that slow down the reaction are called negative catalysts or inhibitors. Substances that increase the [[activity]] of catalysts are called promoters and substances that deactivate catalysts are called catalytic [[poison]]s.
==History==
==History==
In a general sense, anything that increases the rate of a [[process]] is a "catalyst", a term derived from [[Greek]] καταλύειν, meaning "to annul," or "to untie," or "to pick up." The phrase catalysed processes was coined by [http://en.wikipedia.org/wiki/J%C3%B6ns_Jakob_Berzelius Jöns Jakob Berzelius] in 1836 to describe reactions that are accelerated by substances that remain unchanged after the reaction. Other early chemists involved in catalysis were [http://en.wikipedia.org/wiki/Alexander_Mitscherlich Alexander Mitscherlich] who referred to ''contact processes'' and [http://en.wikipedia.org/wiki/Johann_Wolfgang_D%C3%B6bereiner Johann Wolfgang Döbereiner] who spoke of ''contact action'' and whose lighter based on hydrogen and a platinum sponge became a huge commercial success in the 1820s. [http://en.wikipedia.org/wiki/Humphry_Davy Humphry Davy] [[discovered]] the use of platinum in catalysis. In the 1880s, Wilhelm Ostwald at Leipzig University started a systematic investigation into reactions that were catalyzed by the presence of acids and bases, and found that chemical reactions occur at finite rates and that these rates can be used to determine the strengths of acids and bases. For this work, Ostwald was awarded the 1909 [[Nobel Prize]] in Chemistry.
In a general sense, anything that increases the rate of a [[process]] is a "catalyst", a term derived from [[Greek]] καταλύειν, meaning "to annul," or "to untie," or "to pick up." The phrase catalysed processes was coined by [http://en.wikipedia.org/wiki/J%C3%B6ns_Jakob_Berzelius Jöns Jakob Berzelius] in 1836 to describe reactions that are accelerated by substances that remain unchanged after the reaction. Other early chemists involved in catalysis were [http://en.wikipedia.org/wiki/Alexander_Mitscherlich Alexander Mitscherlich] who referred to ''contact processes'' and [http://en.wikipedia.org/wiki/Johann_Wolfgang_D%C3%B6bereiner Johann Wolfgang Döbereiner] who spoke of ''contact action'' and whose lighter based on hydrogen and a platinum sponge became a huge commercial success in the 1820s. [http://en.wikipedia.org/wiki/Humphry_Davy Humphry Davy] [[discovered]] the use of platinum in catalysis. In the 1880s, Wilhelm Ostwald at Leipzig University started a systematic investigation into reactions that were catalyzed by the presence of acids and bases, and found that chemical reactions occur at finite rates and that these rates can be used to determine the strengths of acids and bases. For this work, Ostwald was awarded the 1909 [[Nobel Prize]] in Chemistry.
==Quote==
In those [[suns]] which are encircuited in the [[space]]-[[energy]] [[channels]], [[solar energy]] is liberated by various [[complex]] [http://en.wikipedia.org/wiki/Nuclear_Reaction nuclear-reaction] chains, the most common of which is the hydrogen-carbon-helium reaction. In this [[metamorphosis]], carbon [[acts]] as an [[energy]] [[catalyst]] since it is in no way actually changed by this [[process]] of converting hydrogen into helium. Under certain conditions of high [[temperature]] the hydrogen penetrates the carbon [[nuclei]]. Since the [http://en.wikipedia.org/wiki/Carbon carbon] cannot hold more than four such protons, when this saturation state is [[attained]], it begins to emit protons as fast as new ones arrive. In this [[reaction]] the ingoing hydrogen [[particles]] come forth as a [http://en.wikipedia.org/wiki/Helium helium] [[atom]]. ([[41:8|41:8.1]])
==External links==
==External links==
* [http://scienceaid.co.uk/chemistry/inorganic/catalysis.html Science Aid: Catalysts] Page for high school level science
* [http://scienceaid.co.uk/chemistry/inorganic/catalysis.html Science Aid: Catalysts] Page for high school level science