Wednesday 13 August 2014

Endothermic

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(Redirected from Endothermic reaction)
This COMMODITY is about the concrete effect. For self-maintained thermal homeostasis, see Endotherm.
In thermodynamics, the appellation endothermic describes a action or acknowledgment in which the arrangement absorbs activity from its ambience in the anatomy of heat. The appellation was coined by Marcellin Berthelot from the Greek roots endo-, acquired from the chat "endon" (бј”ОЅОґОїОЅ) acceptation "within" and the basis "therm" (ОёОµПЃОј-) acceptation "hot." The advised faculty is that of a acknowledgment that depends on demography in calefaction if it is to proceed. The adverse of an endothermic action is an exothermic process, one that releases, "gives out" activity in the anatomy of heat. Thus in anniversary appellation (endothermic & exothermic) the prefix refers to area calefaction goes as the acknowledgment occurs.
The abstraction is frequently activated in concrete sciences to, for example, actinic reactions, area thermal activity (heat) is adapted to actinic band energy.
Endothermic (and exothermic) assay alone accounts for the enthalpy (∆H) change of a reaction. The abounding activity assay of a acknowledgment is the Gibbs chargeless activity (∆G), which includes an anarchy (∆S) and temperature appellation in accession to the enthalpy. A acknowledgment could be a Spontaneous action at a assertive temperature if the articles accept a lower absolute chargeless activity (an exergonic reaction) even if the enthalpy of the articles is higher. Anarchy and enthalpy are altered terms, so the change in entropic activity could affected an adverse change in enthalpic energy.
Contents [hide]
1 Contrast amid thermodynamic and biological terminology
2 Examples
3 See also
4 References
5 External links

Contrast between thermodynamic and biological terminology

Because of a actual accident, acceptance appointment a accessible antecedent of abashing amid the analogue of physics and biology. Whereas the thermodynamic agreement "exothermic" and "endothermic" appropriately accredit to processes that accord out calefaction activity and processes that blot calefaction energy, in analysis the faculty is finer inverted. The metabolic agreement "ectothermic" and "endothermic" appropriately accredit to bacilli that await abundantly on alien calefaction to accomplish a abounding alive temperature, and to bacilli that aftermath calefaction from aural as a above agency in authoritative their actual temperature.

Examples

Photosynthesis
Cracking of alkanes
Melting ice
Vaporising Rubbing Alcohol
Thermal atomization reactions
Forming a cation from an atom in the gas phase
Dissolving ammonium chloride in water
High-energy neutrons can aswell aftermath tritium from lithium-7 in an endothermic reaction, arresting 2.466 MeV. This was apparent if the 1954 Castle Bravo nuclear analysis produced an accidentally top yield.[1]
7
3Li + n в†’ 4
2He + 3
1T + n