Wednesday, November 30, 2011

arsenic

  • Question:-ARSENIC??????????????????????????????
    Ok, I already know what arsenic is but what I want is basic information on it, and the site u got it from. Best answer goes to the answerer w/ the most sites (and information)

    Answer:-wiki:
    http://en.wikipedia.org/wiki/Arsenic_poisoning

    cdc:
    http://www.bt.cdc.gov/agent/arsenic/

    http://periodic.lanl.gov/elements/33.html

    all the websites pretty much same the same stuff about arsenic.
  • Question:-arsenic ??


    Answer:-Arsenic
    33 germanium ← arsenic → selenium
    P

    As

    Sb
    Periodic Table - Extended Periodic Table


    General
    Name, Symbol, Number arsenic, As, 33
    Chemical series metalloids
    Group, Period, Block 15, 4, p
    Appearance metallic gray

    Standard atomic weight 74.92160(2)  g·mol−1
    Electron configuration [Ar] 3d10 4s2 4p3
    Electrons per shell 2, 8, 18, 5
    Physical properties
    Phase solid
    Density (near r.t.) 5.727  g·cm−3
    Liquid density at m.p. 5.22  g·cm−3
    Melting point 1090 K
    (817 °C, 1503 °F)
    Boiling point subl. 887 K
    (614 °C, 1137 °F)
    Critical temperature 1673 K
    Heat of fusion (gray) 24.44  kJ·mol−1
    Heat of vaporization ? 34.76  kJ·mol−1
    Heat capacity (25 °C) 24.64  J·mol−1·K−1
    Vapor pressure P(Pa) 1 10 100 1 k 10 k 100 k
    at T(K) 553 596 646 706 781 874

    Atomic properties
    Crystal structure rhombohedral
    Oxidation states 5, 3, 1,[1] -3
    (mildly acidic oxide)
    Electronegativity 2.18 (Pauling scale)
    Ionization energies
    (more) 1st:  947.0  kJ·mol−1
    2nd:  1798  kJ·mol−1
    3rd:  2735  kJ·mol−1
    Atomic radius 115  pm
    Atomic radius (calc.) 114  pm
    Covalent radius 119  pm
    Van der Waals radius 185 pm
    Miscellaneous
    Magnetic ordering no data
    Electrical resistivity (20 °C) 333 n Ω·m
    Thermal conductivity (300 K) 50.2  W·m−1·K−1
    Young's modulus 8  GPa
    Bulk modulus 22  GPa
    Mohs hardness 3.5
    Brinell hardness 1440  MPa
    CAS registry number 7440-38-2
    Selected isotopes
    Main article: Isotopes of arsenic iso NA half-life DM DE (MeV) DP
    73As syn 80.3 d ε - 73Ge
    γ 0.05D, 0.01D, e -
    74As syn 17.78 d ε - 74Ge
    β+ 0.941 74Ge
    γ 0.595, 0.634 -
    β- 1.35, 0.717 74Se
    75As 100% 75As is stable with 42 neutrons

    References
    Arsenic (pronounced /ˈɑrsənɪk/) is a chemical element that has the symbol As and atomic number 33. Arsenic was first written about by Albertus Magnus (Germany) in 1250[2]. Its Atomic Mass is 74.92. Its Ionic Charge is (3-) Its position in the periodic table is shown at right. This is a notoriously poisonous metalloid that has many allotropic forms: yellow (molecular non-metallic) and several black and gray forms (metalloids) are a few that are seen. Three metalloidal forms of arsenic with different crystal structures are found free in nature (the minerals arsenic sensu stricto and the much rarer arsenolamprite and pararsenolamprite), but it is more commonly found as arsenide and arsenate compounds. Several hundred such mineral species are known. Arsenic and its compounds are used as pesticides, herbicides, insecticides and various alloys.

    The most common oxidation states for arsenic are -3 (arsenides: usually alloy-like intermetallic compounds), +3 (arsenates(III) or arsenites, and most organoarsenic compounds), and +5 (arsenates(V): the most stable inorganic arsenic oxycompounds). Arsenic also bonds readily to itself, forming, for instance, As-As pairs in the red sulfide realgar and square As43- ions in the arsenide skutterudite. In the +3 oxidation state, the stereochemistry of arsenic is affected by possession of a lone pair of electrons.


    Notable characteristics
    Arsenic is very similar chemically to its predecessor, phosphorus. Like phosphorus, it forms colourless, odourless, crystalline oxides As2O3 and As2O5 which are hygroscopic and readily soluble in water to form acidic solutions. Arsenic (V) acid, like phosphoric acid, is a weak acid. Like phosphorus, arsenic forms an unstable, gaseous hydride: arsine (AsH3). The similarity is so great that arsenic will partly substitute for phosphorus in biochemical reactions and is thus poisonous. However, in subtoxic doses, soluble arsenic compounds act as stimulants, and were once popular in small doses as medicinals by people in the mid 18th century.

    When heated in air it oxidizes to arsenic trioxide; the fumes from this reaction have an odor resembling garlic. This odor can be detected on striking arsenide minerals such as arsenopyrite with a hammer. Arsenic (and some arsenic compounds) sublimes upon heating at atmospheric pressure, converting directly to a gaseous form without an intervening liquid state. The liquid state appears at 20 atmospheres and above, which explains why the melting point is higher than the boiling point [3]. Elemental arsenic is found in many solid forms: the yellow form is soft, waxy and unstable, and is made of tetrahedral As4 molecules similar to the molecules of white phosphorus. The gray, black or 'metallic' forms have somewhat layered crystal structures with bonds extending throughout the crystal. They are brittle semiconductors with a metallic luster. The density of the yellow form is 1.97 g/cm³; rhombohedral 'gray arsenic' is much denser with a density of 5.73 g/cm³; the other metalloidal forms are similarly dense.


    Applications
    Lead hydrogen arsenate was used well into the 20th century as an insecticide on fruit trees. Its use sometimes resulted in brain damage to those working the sprayers. In the last half century, monosodium methyl arsenate (MSMA), a less toxic organic form of arsenic, has replaced lead arsenate's role in agriculture.

    Scheele's Green, a copper arsenate, was used in the 19th century as a coloring agent in sweets.

    The application of most concern to the general public is probably that of wood treated with chromated copper arsenate, also known as CCA or Tanalith. The vast majority of older pressure-treated wood was treated with CCA. CCA lumber is still in widespread use in many countries, and was heavily used during the latter half of the 20th century as a structural and outdoor building material. It was commonly used in situations where rot or insect infestation was a possibility. Although the use of CCA lumber was banned in many areas after studies showed that arsenic could leach out of the wood into the surrounding soil (from playground equipment, for instance), a risk is also presented by the burning of older CCA timber. The direct or indirect ingestion of wood ash from burnt CCA lumber has caused fatalities in animals and serious poisonings in humans; the lethal human dose is approximately 20 grams of ash. Scrap CCA lumber from construction and demolition sites may be inadvertently used in commercial and domestic fires. Protocols for safe disposal of CCA lumber do not exist evenly throughout the world; there is also concern in some quarters about the widespread landfill disposal of such timber.

    During the 18th, 19th, and 20th centuries, a number of arsenic compounds have been used as medicines, including arsphenamine (by Paul Ehrlich) and arsenic trioxide (by Thomas Fowler). Arsphenamine as well as Neosalvarsan was indicated for syphilis and trypanosomiasis, but has been superseded by modern antibiotics. Arsenic trioxide has been used in a variety of ways over the past 200 years, but most commonly in the treatment of cancer. The US Food and Drug Administration in 2000 approved this compound for the treatment of patients with acute promyelocytic leukemia that is resistant to ATRA.[4] It was also used as Fowler's solution in psoriasis.[5]

    Copper acetoarsenite was used as a green pigment known under many different names, including 'Paris Green' and 'Emerald Green'. It caused numerous arsenic poisonings.

    Other uses;

    Various agricultural insecticides, termination and poisons.
    Used in animal feed, particularly in the US as a method of disease prevention and growth stimulation.
    Gallium arsenide is an important semiconductor material, used in integrated circuits. Circuits made using the compound are much faster (but also much more expensive) than those made in silicon. Unlike silicon it is direct bandgap, and so can be used in laser diodes and LEDs to directly convert electricity into light.
    Also used in bronzing and pyrotechny.
    Occupational Exposures

    Exposure to higher-than-average levels of arsenic can occur in some occupations placing workers at risk. Industries that use inorganic arsenic and its compounds include wood preservation, glass production, nonferrous metal alloys, and electronic semiconductor manufacturing. Inorganic arsenic is also found in coke oven emissions associated with the smelter industry. [6]


    History
    The word arsenic is borrowed from the Persian word زرنيخ Zarnikh meaning "yellow orpiment". Zarnikh was borrowed by Greek as arsenikon, which means masculine or potent. Arsenic has been known and used in Persia and elsewhere since ancient times. As the symptoms of arsenic poisoning were somewhat ill-defined, it was frequently used for murder until the advent of the Marsh test, a sensitive chemical test for its presence. (Another less sensitive but more general test is the Reinsch test.) Due to its use by the ruling class to murder one another and its potency and discreetness, arsenic has been called the Poison of Kings and the King of Poisons.

    During the Bronze Age, arsenic was often included in bronze, which made the alloy harder (so-called "arsenical bronze").

    Albertus Magnus (Albert the Great, 1193-1280) is believed to have been the first to isolate the element in 1250[2]. In 1649 Johann Schröder published two ways of preparing arsenic.


    Alchemical symbol for arsenicIn the Victorian era, 'arsenic' (colourless, crystalline, soluble 'white arsenic') was mixed with vinegar and chalk and eaten by women to improve the complexion of their faces, making their skin paler to show they did not work in the fields. Arsenic was also rubbed into the faces and arms of women to 'improve their complexion'. The accidental use of arsenic in the adulteration of foodstuffs led to the Bradford sweet poisoning in 1858, which resulted in approximately 20 deaths and 200 people taken ill with arsenic poisoning.

    Occurrence

    A large sample of native a
  • Question:-Arsenic??????????????????????????????????????
    ok i need to know alot about it any info

    Answer:-Arsenic (pronounced /ˈɑrsənɪk/) is a chemical element that has the symbol As and atomic number of 33. Arsenic was first documented by Albertus Magnus in 1250[2]. Its Atomic Mass is 74.92. Its position in the periodic table is shown at right. This is a notoriously poisonous metalloid that has many allotropic forms: yellow (molecular non-metallic) and several black and grey forms (metalloids) are a few that are seen. Three metalloidal forms of arsenic with different crystal structures are found free in nature (the minerals arsenic sensu stricto and the much rarer arsenolamprite and pararsenolamprite), but it is more commonly found as arsenide and arsenate compounds. Several hundred such mineral species are known. Arsenic and its compounds are used as pesticides, herbicides, insecticides and various alloys.

    The most common oxidation states for arsenic are -3 (arsenides: usually alloy-like intermetallic compounds), +3 (arsenates(III) or arsenites, and most organoarsenic compounds), and +5 (arsenates(V): the most stable inorganic arsenic oxycompounds). Arsenic also bonds readily to itself, forming, for instance, As-As pairs in the red sulfide realgar and square As43- ions in the arsenide skutterudite. In the +3 oxidation state, the stereochemistry of arsenic is affected by possession of a lone pair of electrons.
  • Question:-How much arsenic is needed to kill someone?
    I'm working on a novel, and a character is plotting to put arsenic in a bottle of communion wine. How much arsenic would be needed to poison and kill someone who has just a sip or two from the bottle? Would you be able to taste the arsenic?

    Answer:-about 600g at one time but it's easy to detect. Most people who kill with it use it over time so in the autopsy, there aren't abnormal amounts detected in the body.
  • Question:-How much arsenic would it take to kill?
    In most murder mystery's, arsenic is used to kill people.
    But how much would be needed? Heck, what is arsenic?

    Answer:-763 mg/kg (by ingestion) and 13 mg/kg (by intraperitoneal injection).
  • Question:-Arsenic in a ant trap. Does it matter how much is ingested before a pet might have problems or worse?
    The ant trap had 2% percent of arsenic in it. My dog is a golden retriever whose 3 months old and weighs 35 pounds. I'm not sure how much poison was in the ant trap and how much my pup managed to get into his body. Plus for how long he first came in contact with it before I could get him to the vet. I'm really distraught over this and don't wanna lose him.

    Answer:-Here is some information on ant traps w/arsenic, and pet poisoning. It has some figures on how much is how toxic per lbs of weight of the dog.

    http://www.petplace.com/dogs/arsenic-poisoning/page1.aspx

    If you've gotten him to the vet, its the best thing you could do. Good luck, I hope he's ok.
  • Question:-How much Arsenic would it take to kill someone?
    I need to know how much arsenic will kill the average person over a period of one month. I also need to know how much arsenic will kill the average person within a couple of days. I need this information for a Forensic Science research project.
    Thank You.

    Answer:-To find the answer to that, research books about toxicology and find the LD (lethal dosage) of arsenic. If you are truly doing a research project go to the library and find the journal of forensic science, they might have research on this already. There are tons of journals/books in Forensic Science. Ask help from your university librarian and I'm sure you will find lots of info. If I was your teacher (I taught a course in FS) I would not allow you to use Yahoo Answers as your reference point. Actually I only allowed 2 internet resources since our students seem to have trouble differentiation from a reliable source and one that was not.
  • Question:-Is there anyway to tell, without using an arsenic testing kit, if wood has been treated with arsenic or not?
    Are there any visual indications one might go off of? Would the wood have an irregular color? Was arsenic only applied to lumber for things like decks? How do I know?

    Answer:-If it is an outdoor wood structure built prior to 2004 then, yes, it was pressure treated with arsenic. No exceptions. Your exposure is greatly reduced by making sure your deck or structure is sealed with a stain or paint frequently. Else if you are highly concerned then you would need to replace the wood.
  • Question:-What is the chemical equation for arsenic?
    If it helps, the question on my assignment sheet it "How is your element produced? Include a chemical equation." I'm not really sure what that means, but i guess where arsenic is the product of two other things?
    Thanks.

    Answer:-Arsenic is produce by heating arsenic-bearing minerals in the absence of air. E.g.


    FeAs2--------------->FeS +As(g)------------>As(s)
    (at 700 celcius)
  • Question:-What are the physical properties of arsenic?
    I can't find any website that will give me the physical properties of arsenic without them giving me a whole bunch of reactions and such.

    Answer:-It pains me to admit it but Wikipedia does a good job.

    See http://en.wikipedia.org/wiki/Arsenic

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