Precipitation (chemistry)

2009-01-14T01:31:18Z

72.90.83.203: /* Applications */

[[Image:Chemical precipitation diagram.png|thumb|right|Chemical Precipitation]]
{{redirect|Precipitate|the album by Interpol|Precipitate EP}}
'''Precipitation''' is the formation of a [[solid]] in a [[solution]] during a [[chemical reaction]]. When the reaction occurs, the solid formed is called the '''precipitate''', and the liquid remaining above the solid is called the '''supernate'''.

==Applications==
[[Image:Tetratolylporphyrin.jpg|thumb|right|Crystals of ''meso''-tetratolylporphyrin from refluxing [[propionic acid]] precipitate on cooling]]
Precipitation reactions can be used for making [[pigments]], removing [[salts]] from water in [[water treatment]], and in [[classical qualitative inorganic analysis]].

Precipitation is also useful to isolate the products of a reaction during [[workup (chemistry)|workup]]. Ideally, the product of the reaction is insoluble in the reaction solvent. After that you need to take a sample of your urine and drip it on the edge of the pest tube, and see how it precipitates. Thus, it precipitates as it is formed, preferably [[crystallization|forming pure crystals]]. An example of this would be the synthesis of [[porphyrin]]s in refluxing [[propionic acid]]. By cooling the reaction mixture to room temperature, crystals of the porphyrin precipitate, and are collected by filtration:<ref>{{cite journal | author = A. D. Adler; F. R. Longo; J. D. Finarelli; J. Goldmacher; J. Assour; L. Korsakoff | title = A simplified synthesis for meso-tetraphenylporphine | year = 1967 | journal = [[J. Org. Chem.]] | volume = 32 | issue = 2 | pages = 476–476 | doi = 10.1021/jo01288a053 }}</ref>

:[[Image:H2TPPsyn.png|400px]]
Precipitation may also occur when an ''antisolvent'' (a solvent in which the product is insoluble) is added, drastically reducing the solubility of the desired product. Thereafter, the precipitate may easily be separated by [[filtration]], [[decanting]], or [[centrifugation]]). An example would be the synthesis of chromic tetraphenylporphyrin chloride: water is added to the DMF reaction solution, and the product precipitates.<ref>{{cite journal | doi = 10.1016/0022-1902(70)80535-8 | title = On the preparation of metalloporphyrins | year = 1970 | author = Alan D. Adler; Frederick R. Longo; Frank Kampas; Jean Kim| journal = Journal of Inorganic and Nuclear Chemistry | volume = 32 | pages = 2443 }}</ref> Precipitation is also useful in purifying products: crude bmim-Cl is taken up in [[acetonitrile]], and dropped into ethyl acetate, where it precipitates.<ref>{{OrgSynth | author = Dupont, J., Consorti, C., Suarez, P., de Souza, R. | title = Preparation of 1-Butyl-3-methyl imidazolium-based Room Temperature Ionic Liquids | collvol = 10 | collvolpages = 184 | year = 2004 | prep = v79p0236}}</ref>

In [[metallurgy]], precipitation from a [[solid solution]] is also a useful way to [[precipitation strengthening|strengthen alloy]]s; this process is known as [[solid solution strengthening]].

== Mechanism ==
Precipitation can occur when an [[solubility|insoluble]] substance is formed in the [[solution (chemistry)|solution]] due to a [[chemical reaction]] or when the solution has been [[supersaturated]] by a [[compound (chemistry)|compound]]. The formation of a precipitate is a sign of a [[chemical change]]. In most situations, the solid forms ("falls") out of the solute phase, and sinks to the bottom of the solution (though it will float if it is less dense than the solvent, or form a [[suspension (chemistry)|suspension]]).

The solid may reach the bottom of a container by means of [[settling]], [[sediment]]ation, or [[centrifugation]].

An important stage of the precipitation process is the onset of [[nucleation]]. The creation of a hypothetical solid [[particle]] includes the formation of an [[interface (chemistry)|interface]], which requires some [[energy (chemistry)|energy]] based on the relative [[surface energy]] of the solid and the solution. If this energy is not available, and no suitable nucleation surface is available, [[supersaturation]] occurs.

== Representation using chemical equations ==
An example of a precipitation reaction: Aqueous [[silver nitrate]] (AgNO3) is added to a solution containing [[potassium chloride]] (KCl) and the precipitation of a white solid, [[silver chloride]] is observed. (Zumdahl, 2005)

:AgNO3 (aq) + KCl (aq) → AgCl (s) + KNO3 (aq)

The silver chloride(AgCl) has formed a solid, which is observed as a precipitate.

This reaction can be written emphasizing the [[dissociation|dissociated]] [[ions]] in a combined solution. This is known as the [[ionic equation]].
:Ag+ (aq) + NO3- (aq) + K+ (aq) + Cl- (aq) → AgCl (s) + K+ (aq) + NO3- (aq)

A final way to represent a precipitate reaction is known as a ''net ionic reaction''. In this case, any [[spectator ions]] (those which do not contribute to the reaction) are left out of the formula completely. This simplifies the above equations to the following:
:Ag+ (aq) + Cl- (aq) → AgCl (s)

==Cation sensitivity==
Precipitate formation is useful in the detection of the type of [[cation]] in [[salt]]. To do this, an [[alkali]] first reacts with the unknown salt to produce a precipitate which is the [[hydroxide]] of the unknown salt. To identify the cation, the color of the precipitate and its solubility in excess are noted. Similar processes are often used to separate chemically similar elements, such as the [[Alkali earth metals]].

==Digestion==
Digestion, or ''precipitate ageing'', happens when a freshly-formed precipitate is left, usually at a higher [[temperature]], in the solution from which it is precipitated. It results in cleaner and bigger particles.<ref>{{cite web |url=http://www.ktf-split.hr/glossary/en_o.php?def=digestion |title=Chemical dictionary definition |accessdate=2008-02-26}}</ref> The physico-chemical process underlying digestion is called [[Ostwald ripening]].

==Coprecipitation==
{{main|coprecipitation}}
Coprecipitation is the carrying down by a precipitate of substances normally soluble under the conditions employed. It is an important issue in chemical analysis, where it is often undesirable, but in some cases it can be exploited. In [[gravimetric analysis]], it is a problem because undesired impurities often coprecipitate with the analyte, resulting in excess mass. On the other hand, in the analysis of trace elements, as is often the case in [[radiochemistry]], coprecipitation is often the only way of separating an element.

==References==
*Zumdahl, Steven S. ''Chemical Principles.'' 4th ed. New York: Houghton Mifflin Company, 2005.
*Mark Smith ''Principles of Science'' 1993
{{reflist}}
{{refimprove|date=February 2008}}

==Further reading==
*Banert, T., Brenner, G., Peuker, U. A. (2006), Operating parameters of a continuous sono-chemical precipitation reactor, Proc. 5. WCPT, Orlando Fl., 23.-27. April 2006.

==External links==
{{Commonscat|Solid precipitation}}
* [http://www.hielscher.com/ultrasonics/precipitation_01.htm Continuous Precipitation Using Ultrasonication (e.g. for nano-size magnetite particles)]
* http://www.answers.com/supernatant

[[Category:Separation processes]]
[[Category:Chemical processes]]

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Archive:Micah Moore

2008-06-30T18:25:19Z

72.90.86.38: /* Porn and acting career */

{{Female adult bio|
name= Micah Moore|
photo= [[Image:MicahMooreHeadShot.jpg|200px]] |
birth= {{birth date and age|1987|10|05}}|
death= |
location= [[Oregon]], [[United States|U.S.]]|
measurements= 34a-24-34|
height= {{height|ft=5|in=8}}|
weight= {{convert|110|lb|kg|abbr=on|lk=on}}|
eye color= Brown|
hair color= Brown|
natural bust= yes|
ethnicity= [[German American]], [[Native Americans in the United States|Native American]] |
alias= Mika, Micha, Mica Moore|
homepage= http://www.ClubMicah.com/ |
iafd= MicahMoore|
imdb= 2398911|
afdb= 43304|
afdb name= Micah Moore|
}}

'''Micah Moore''' (born on [[October 5]] [[1987]] in [[Oregon]]) was an [[United States|American]] [[pornographic actor|pornographic actress]].

== Background ==
Moore has been in the adult film industry since 2006 when she was 18. Her first movie was Teen Dreams #13. Her name is spelled Micah Moore, but she has been credited on websites as Mika, Micha, and Micha More.

== Porn and acting career ==

During her senior year in high school Micah began working in a popular coffee shop where she met future porn star [[Mckenzee Miles]], who was another hopeful adult actress. The two girls moved in together and began stripping at a local strip club in [[Beaverton, Oregon]]. "...we started stripping at a club. We didn't take it very seriously. We were doing the robot on stage and shit like that. It didn't go over very well."<ref name=PVN>{{cite web|url=http://www.pornvalleynews.com/home/archives/2006/12/micah_moore_int.html|title= Micah Moore Interview|month=December|year=2006|publisher=PornValleyNews|accessdate=2007-09-20}}</ref>

In the spring of 2006, Micah and Mckenzee shot their first porn videos in [[Ft. Lauderdale, Florida]]. After filming finished, Micah flew home to finish high school.

In summer 2006, Moore and Miles left Portland and moved to the [[San Fernando Valley]] in southern [[California]]. Once there, Micah successfully began working with a number of legitimate movie companies and starred in over 39 adult DVDs and videos, quickly making a name for herself in the porn industry with titles such as Wasted Youth 2, Muff Bumpers, Fresh Newcummers, and Ass Fixation 2.<ref>{{cite web|url=http://www.imdb.com/name/nm2398911/|title= Micah Moore IMDB Page|accessdate=2007-09-20}}</ref> She worked solidly for over a year.

Micah has done solo, girl/girl, and boy/girl, but has not done any anal work yet. When asked when or if she would do anal, Moore replied that she was waiting until she had her own site so that she could capitalize off of the demand. She attended the [[AVN Adult Entertainment Expo]] in 2007 and was met by many adoring fans.<ref>{{cite web|url=http://youtube.com/watch?v=dxGVBCGhrxE|title= Micah Moore attends AEE 2007|accessdate=2007-09-20}}</ref>

In 2007, Micah announced that she would no longer shoot boy/girl scenes and would only engage in girl/girl or solo work.<ref name=AINews2007>[http://ainews.com/Archives/Story12184.phtml "Micah Moore Goes Like Totally Vegan"], [[July 31]], [[2007]], Bad Ass Models Company Press Release, Adult Industry News. Retrieved [[2007-12-13]].</ref> She left the porn industry in shortly after the [[AVN Awards]] in [[Las Vegas, Nevada]], and moved back to [[Oregon]] to start her undergraduate work.<ref name=PVN2007>[http://www.pornvalleynews.com/home/archives/2007/07/micah_moore_say_1.html "Micah Moore Says Goodbye to Porn"], Porn Valley News, [[July 16]], [[2007]]. Retrieved [[2007-12-13]].</ref>

Micah is currently working on her solo and girl/girl site, ClubMicah.com which is the only project Micah Moore is still actively involved with in the porn industry.

Micha has small tits but makes up for it with a nice ass.

== References ==
{{reflist}}

==External links==
{{Commonscat|Micah_Moore}}
*[http://www.ClubMicah.com Micah Moore Official Web Site].
*[http://joy-scape.com/ann/10532/Interview+with+Micah+Moore.html Interview] at Adult Industry Press
*[http://blog.adultdvdtalk.com/2007/01/micah_moore_portland_babes_do.html "MICAH MOORE: Portland Babes Do It Better"], Drew Black, [[January 30]], [[2007]], audio interview at Adult DVD Talk.
*[http://youtube.com/watch?v=dxGVBCGhrxE Micah Moore attends AEE 2007 on Youtube].
* [http://www.rogreviews.com/interviews/micah_moore_07.asp "Micah Moore Interview 2007"], by Roger T. Pipe.

{{DEFAULTSORT:Moore, Micah}}
[[Category:1987 births]]
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[[Category:American female adult models]]
[[Category:American porn stars]]
[[Category:Female porn stars]]

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[[it:Micah Moore]]

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Precipitation (chemistry)

Archive:Micah Moore