Arsenic - Revision history

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Jmdonev at 02:46, 21 November 2016

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← Older revision		Revision as of 02:46, 21 November 2016
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	[[Category:Done ~~2015~~-09-05]]		[[Category:Done 2016-12-31]]
	[[File:ARSENIC.png\|200px\|thumb\|Figure 1. Arsenic, [[atomic number]] of 33 and [[atomic weight]] of 74.9216.<ref name=pt>PeriodicTable. (August 25, 2015). ''Arsenic'' [Online], Available: http://periodictable.com/Elements/033/</ref>]]		[[File:ARSENIC.png\|200px\|thumb\|Figure 1. Arsenic, [[atomic number]] of 33 and [[atomic weight]] of 74.9216.<ref name=pt>PeriodicTable. (August 25, 2015). ''Arsenic'' [Online], Available: http://periodictable.com/Elements/033/</ref>]]
			[[File:Arsenic.jpg\|200px\|thumb\|Figure 2. Arsenic crystal.<ref>Arsenic [[Online]], Available: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0 [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons</ref>]]

	<onlyinclude>'''Arsenic''' ('''As''') is the 33<sup>rd</sup> [[element]] on the [[periodic table of elements\|periodic table]], and is found naturally in trace amounts on Earth. It is most often found combined with other elements, but is also found in its pure form.</onlyinclude><ref name=jl>Jefferson Labs. (August 25, 2015). ''The Element Arsenic'' [Online], Available: http://education.jlab.org/itselemental/ele033.html</ref> Historically it was the poison of choice until its detection became easy.<ref name=pt/> It is still used today as a poison for rats and pests, in a strictly controlled manner.<ref name=rsc>Royal Society of Chemistry. (August 25, 2015). ''Arsenic'' [Online], Available: http://www.rsc.org/periodic-table/element/33/arsenic</ref>		<onlyinclude>'''Arsenic''' ('''As''') is the 33<sup>rd</sup> [[element]] on the [[periodic table of elements\|periodic table]], and is found naturally in trace amounts on Earth. It is most often found combined with other elements, but is also found in its pure form.</onlyinclude><ref name=jl>Jefferson Labs. (August 25, 2015). ''The Element Arsenic'' [Online], Available: http://education.jlab.org/itselemental/ele033.html</ref> Historically, it was the poison of choice until its detection became easy.<ref name=pt/> It is still used today as a poison for rats and pests, in a strictly controlled manner.<ref name=rsc>Royal Society of Chemistry. (August 25, 2015). ''Arsenic'' [Online], Available: http://www.rsc.org/periodic-table/element/33/arsenic</ref>

	Arsenic also forms a [[semiconductor]] when combined with [[gallium]], used for integrated circuits in supercomputers and other forms of [[technology]].<ref name=rsc/>		Arsenic also forms a [[semiconductor]] when combined with [[gallium]], used for integrated circuits in supercomputers and other forms of [[technology]].<ref name=rsc/>
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	<nowiki>*</nowiki>'''Note''': The boiling point is actually ''lower'' than the melting point because arsenic [[phase change\|change phases]] directly from a [[solid]] to a [[gas]] under normal [[atmospheric pressure]]. It requires ~~immense~~ pressures of 28 atm in order to phase change from a solid to a [[liquid]], hence the higher [[temperature]].<Ref name=jl/>		<nowiki>*</nowiki>'''Note''': The boiling point is actually ''lower'' than the melting point because arsenic [[phase change\|change phases]] directly from a [[solid]] to a [[gas]] under normal [[atmospheric pressure]]. It requires pressures of 28 atm in order to phase change from a solid to a [[liquid]], hence the higher [[temperature]].<Ref name=jl/>

	==Emissions of arsenic==		==Emissions of arsenic==
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	Arsenic is emitted from various energy related sources. It can be emitted from external combustion [[boiler]]s, [[copper]] and [[zinc]] [[smelting]], copper mining, [[uranium mining]], and [[lead]] smelting. It may also arise from waste incineration and glass manufacturing.<ref name=epa/>		Arsenic is emitted from various energy related sources. It can be emitted from external combustion [[boiler]]s, [[copper]] and [[zinc]] [[smelting]], copper mining, [[uranium mining]], and [[lead]] smelting. It may also arise from waste incineration and glass manufacturing.<ref name=epa/>

	Emissions of arsenic from these sources is caused by the trace amount of arsenic in the ~~fuels~~ they use and the materials they process. The actual amount of arsenic emitted varies quite considerably, for instance the emissions of arsenic contained in [[coal]] may vary up to 4 orders of magnitude.<ref name=epa>Environmental Protection Agency. (August 26, 2015). ''LOCATING AND ESTIMATING AIR EMISSIONS FROM SOURCES OF ARSENIC AND ARSENIC COMPOUNDS'' [Online], Available: http://www.epa.gov/ttnchie1/le/arsenic.pdf</ref>		Emissions of arsenic from these sources is caused by the trace amount of arsenic in the [[fuel]]s they use and the materials they process. The actual amount of arsenic emitted varies quite considerably, for instance the emissions of arsenic contained in [[coal]] may vary up to 4 orders of magnitude.<ref name=epa>Environmental Protection Agency. (August 26, 2015). ''LOCATING AND ESTIMATING AIR EMISSIONS FROM SOURCES OF ARSENIC AND ARSENIC COMPOUNDS'' [Online], Available: http://www.epa.gov/ttnchie1/le/arsenic.pdf</ref>

	==Toxicity==		==Toxicity==

	Arsenic is relatively safe in its [[organic molecule\|organic form]] (bound to [[carbon]]), however it is extremely toxic in its inorganic form.<ref name=who>World Health Organization. (August 25, 2015). ''Arsenic'' [Online], Available: http://www.who.int/mediacentre/factsheets/fs372/en/</ref> Organic arsenic is often found in seafood and at safe levels. Inorganic arsenic is found in groundwater in high amounts in some countries around the world, or in the air as [[pollution]]. People may be exposed to arsenic through contaminated water. This can be a problem if water with arsenic is drank, used for food preparation, or raising crops. Smoking tobacco and some industrial processes also expose people to arsenic.<ref name=who/>		Arsenic is relatively safe in its [[organic molecule\|organic form]] (bound to [[carbon]]), however it is extremely toxic in its inorganic form.<ref name=who>World Health Organization. (August 25, 2015). ''Arsenic'' [Online], Available: http://www.who.int/mediacentre/factsheets/fs372/en/</ref> Organic arsenic is often found in seafood and at safe levels. Inorganic arsenic is found in groundwater in high amounts in some countries around the world, or in the air as [[pollution]]. People may be exposed to arsenic through contaminated [[water]]. This can be a problem if water with arsenic is drank, used for food preparation, or raising crops. Smoking tobacco and some industrial processes also expose people to arsenic.<ref name=who/>

	Drinking [[water]] contaminated with arsenic can lead to chronic arsenic poisoning, with skin lesions and skin cancer being the most common effects.<Ref name=who/>		Drinking [[water]] contaminated with arsenic can lead to chronic arsenic poisoning, with skin lesions and skin cancer being the most common effects.<Ref name=who/>
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	<center>'''Visit the [http://www.epa.gov/teach/chem_summ/Arsenic_summary.pdf EPA] for more information about arsenic.'''</center>		<center>'''Visit the [http://www.epa.gov/teach/chem_summ/Arsenic_summary.pdf EPA] for more information about arsenic.'''</center>

			==Video==
			The video below is from the University of Nottingham's [http://www.periodicvideos.com/ periodic videos project].<ref>See more videos from the University of Nottingham on different elements here: http://www.periodicvideos.com/</ref> They have created a complete suite of short videos on every element on the [[periodic table of elements]].

			<html>
			<iframe width="816" height="459" src="https://www.youtube.com/embed/a2AbKwAvyos" frameborder="0" allowfullscreen></iframe>
			</html>

	==References==		==References==
	{{reflist}}		{{reflist}}[[Category:Uploaded]]
			[[category: Ian edit]]

J.williams: 1 revision imported

2015-09-03T18:22:24Z

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Jmdonev at 22:37, 27 August 2015

2015-08-27T22:37:57Z

New page

[[Category:Done 2015-09-05]]
[[File:ARSENIC.png|200px|thumb|Figure 1. Arsenic, [[atomic number]] of 33 and [[atomic weight]] of 74.9216.<ref name=pt>PeriodicTable. (August 25, 2015). ''Arsenic'' [Online], Available: http://periodictable.com/Elements/033/</ref>]]

<onlyinclude>'''Arsenic''' ('''As''') is the 33rd [[element]] on the [[periodic table of elements|periodic table]], and is found naturally in trace amounts on Earth. It is most often found combined with other elements, but is also found in its pure form.</onlyinclude><ref name=jl>Jefferson Labs. (August 25, 2015). ''The Element Arsenic'' [Online], Available: http://education.jlab.org/itselemental/ele033.html</ref> Historically it was the poison of choice until its detection became easy.<ref name=pt/> It is still used today as a poison for rats and pests, in a strictly controlled manner.<ref name=rsc>Royal Society of Chemistry. (August 25, 2015). ''Arsenic'' [Online], Available: http://www.rsc.org/periodic-table/element/33/arsenic</ref>

Arsenic also forms a [[semiconductor]] when combined with [[gallium]], used for integrated circuits in supercomputers and other forms of [[technology]].<ref name=rsc/>

Some properties of arsenic include:<Ref name=jl/>

{| class="wikitable"
|-
| '''[[Atomic weight]]''' || 74.9216
|-
| '''[[Density]]''' (at 0oC) || 5.776 [[gram|g]]/[[centimeter|cm3]]
|-
| '''[[Boiling point]]'''* || 887 [[Kelvin|K]]
|-
| '''[[Melting point]]''' (at 28 [[atm]]) || 1090 K
|}

<nowiki>*</nowiki>'''Note''': The boiling point is actually ''lower'' than the melting point because arsenic [[phase change|change phases]] directly from a [[solid]] to a [[gas]] under normal [[atmospheric pressure]]. It requires immense pressures of 28 atm in order to phase change from a solid to a [[liquid]], hence the higher [[temperature]].<Ref name=jl/>

==Emissions of arsenic==

Arsenic is emitted from various energy related sources. It can be emitted from external combustion [[boiler]]s, [[copper]] and [[zinc]] [[smelting]], copper mining, [[uranium mining]], and [[lead]] smelting. It may also arise from waste incineration and glass manufacturing.<ref name=epa/>

Emissions of arsenic from these sources is caused by the trace amount of arsenic in the fuels they use and the materials they process. The actual amount of arsenic emitted varies quite considerably, for instance the emissions of arsenic contained in [[coal]] may vary up to 4 orders of magnitude.<ref name=epa>Environmental Protection Agency. (August 26, 2015). ''LOCATING AND ESTIMATING AIR EMISSIONS FROM SOURCES OF ARSENIC AND ARSENIC COMPOUNDS'' [Online], Available: http://www.epa.gov/ttnchie1/le/arsenic.pdf</ref>

==Toxicity==

Arsenic is relatively safe in its [[organic molecule|organic form]] (bound to [[carbon]]), however it is extremely toxic in its inorganic form.<ref name=who>World Health Organization. (August 25, 2015). ''Arsenic'' [Online], Available: http://www.who.int/mediacentre/factsheets/fs372/en/</ref> Organic arsenic is often found in seafood and at safe levels. Inorganic arsenic is found in groundwater in high amounts in some countries around the world, or in the air as [[pollution]]. People may be exposed to arsenic through contaminated water. This can be a problem if water with arsenic is drank, used for food preparation, or raising crops. Smoking tobacco and some industrial processes also expose people to arsenic.<ref name=who/>

Drinking [[water]] contaminated with arsenic can lead to chronic arsenic poisoning, with skin lesions and skin cancer being the most common effects.<Ref name=who/>

===Effects===

Acute effects (short term) include vomiting, abdominal pain, and diarrhea. Numbness of extremities may occur shortly after, and even possibly death.

Long-term effects can often be observed on the skin, typically after 5 or more years of exposure, including skin pigmentation, lesions, and hard spots on the palms and feet, all of which may be precursors for skin cancer. Lung and bladder cancer may also be attributed to chronic arsenic exposure. Other effects include neurotoxicity, development problems, diabetes, and cardiovascular disease.<ref name=who/>

The World Health Organization's guideline for maximum dose is 10 [[gram|μg]]/[[liter]], yet some nations experience doses over 5 times that amount. It is still difficult to gauge how big of a problem arsenic is however, since it is hard to isolate its effects compared to other external factors. Even so, it is still of major concern around the world.<ref name=who/>

<center>'''Visit the [http://www.epa.gov/teach/chem_summ/Arsenic_summary.pdf EPA] for more information about arsenic.'''</center>

==References==
{{reflist}}