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Supplier Related Products Identification Chemical Properties Safety Data Raw materials And Preparation Products Hazard Information Material Safety Data Sheet(MSDS) Well-known Reagent Company Product Information

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Molecular Formula
MDL Number
Molecular Weight
MOL File

Chemical Properties

A nonmetallic element of atomic number 33, group Va of periodic table, aw 74.9216, valences of 2, 3, 5; no stable isotopes.
Elemental arsenic, as, occurs to a limited extent in nature as a steel-gray, amorphous metalloid.
grey powder or chunks
817 °C(lit.)

613 °C(lit.)

5.727 g/mL at 25 °C(lit.)


Stable. Incompatible with acids, oxidizing agents, halogens. Heat and air-sensitive.
Water Solubility 
Elemental arsenic occurs in two solid modifications: yellow, and gray or metallic, with specific gravities of 1.97, and 5.75, respectively. Gray arsenic, the ordinary stable form, has a triple point of 817°C and sublimes at 616°C and has a critical temperature of 1400°C. Several other allotropic forms of arsenic are reported in the literature. It is believed that Albertus Magnus obtained the element in 1250 A.D. In 1649 Schroeder published two methods of preparing the element. It is found native, in the sulfides realgar and orpiment, as arsenides and sulfarsenides of heavy metals, as the oxide, and as arsenates. Mispickel, arsenopyrite, (FeSAs) is the most common mineral, from which on heating the arsenic sublimes leaving ferrous sulfide. The element is a steel gray, very brittle, crystalline, semimetallic solid; it tarnishes in air, and when heated is rapidly oxidized to arsenous oxide (As2O3) with the odor of garlic. Arsenic and its compounds are poisonous. Exposure to arsenic and its compounds should not exceed 0.01 mg/m3 as elemental As during an 8-h work day. Arsenic is also used in bronzing, pyrotechny, and for hardening and improving the sphericity of shot. The most important compounds are white arsenic (As2O3), the sulfide, Paris green 3Cu(AsO2)2· Cu(C2H3O2)2, calcium arsenate, and lead arsenate; the last three have been used as agricultural insecticides and poisons. Marsh’s test makes use of the formation and ready decomposition of arsine (AsH3). Arsenic is available in high-purity form. It is finding increasing uses as a doping agent in solid-state devices such as transistors. Gallium arsenide is used as a laser material to convert electricity directly into coherent light. Natural arsenic is made of one isotope 75As. Thirty other radioactive isotopes and isomers are known. Arsenic (99%) costs about $75/50g. Purified arsenic (99.9995%) costs about $50/g.
CAS DataBase Reference
7440-38-2(CAS DataBase Reference)
NIST Chemistry Reference
EPA Substance Registry System
7440-38-2(EPA Substance)

Safety Data

Hazard Codes 
Risk Statements 
R23/25:Toxic by inhalation and if swallowed .
R50/53:Very Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment .
R36/38:Irritating to eyes and skin .
R22:Harmful if swallowed.
R45:May cause cancer.
Safety Statements 
S20/21:When using, do not eat, drink or smoke .
S28:After contact with skin, wash immediately with plenty of ... (to be specified by the manufacturer) .
S45:In case of accident or if you feel unwell, seek medical advice immediately (show label where possible) .
S60:This material and/or its container must be disposed of as hazardous waste .
S61:Avoid release to the environment. Refer to special instructions safety data sheet .
S26:In case of contact with eyes, rinse immediately with plenty of water and seek medical advice .
S53:Avoid exposure-obtain special instruction before use .
UN 1558 6.1/PG 2

WGK Germany 


HS Code 
Safety Profile
Confirmed human carcinogen producing liver tumors. Poison by subcutaneous, intramuscular, and intraperitoneal routes. Human systemic skin and gastrointestinal effects by ingestion. An experimental teratogen. Other experimental reproductive effects. Mutation data reported. Flammable in the form of dust when exposed to heat or flame or by chemical reaction with powerful oxidizers such as bromates, chlorates, iodates, peroxides, lithium, NC4, m 0 3 , Khfn04, Rb2C2, AgN04, NOCl, IF5, CrO3, CIF3, Cl0, BrF3, BrFj, BrN3, RbGBCH, CsC3BCH. Slightly explosive in the form of dust when exposed to flame. When heated or on contact with acid or acid fumes, it emits highly toxic fumes; can react vigorously on contact with oxidizing materials. Incompatible with bromine azide, dirubidium acetylide, halogens, palladium, zinc, platinum, NCh, AgNO3, CrO3, Na2O2, hexafluoroisopropylideneamino lithum.
Hazardous Substances Data
7440-38-2(Hazardous Substances Data)

Raw materials And Preparation Products

Hazard Information

General Description
A grayish metallic solid that turns black upon exposure to air. Insoluble in water. Toxic by ingestion.
Reactivity Profile
ARSENIC(7440-38-2) reacts incandescently with bromine trifluoride, even at 10°C [Mellor 2:113 1946-47]. Causes bromoazide to explode upon contact. Ignites if ground up together with solid potassium permanganate [Mellor 12:322 1946-47]. Is oxidized by sodium peroxide with incandescence [Mellor 2:490-93 1946-47]. A combination of finely divided ARSENIC(7440-38-2) with finely divided bromates (also chlorates and iodates) of barium, calcium, magnesium, potassium, sodium, or zinc can explode by heat, percussion, and friction [Mellor 2:310 1946-47]. Bromine pentafluoride reacts readily in the cold with ARSENIC(7440-38-2). Ignition usually occurs. Reacts vigorously with fluorine at ordinary temperatures [Mellor 9:34 1946-47].
Air & Water Reactions
Turns black on exposure to air. Insoluble in water.
Confirmed carcinogen and mutagen. OSHA employee exposure limit:
Health Hazard
Poisonous by inhalation of dust or by ingestion. Regardless of exposure route, symptoms in most cases are characteristic of severe gastritis or gastroenteritis. All chemical forms of arsenic eventually produce similar toxic effects. Symptoms may be delayed.
Potential Exposure
Arsenic compounds have a variety of uses. Arsenic and its compounds are used as an alloy additive, in electronic devices; in veterinary medicines; in agriculture as insecticides, herbicides, larvicides, and pesticides. Some arsenic compounds are used in pigment production; the manufacture of glass as a bronzing or decolorizing agent; the manufacture of opal glass and enamels, textile printing; tanning, taxidermy, antifouling paints; to control sludge formation in lubricating oils. Metallic arsenic is used as an alloying agent for heavy metals; and in solders, medicines, herbicides. EPA has estimated that more than 6 million people living within 12 mi of major sources of copper, zinc, and lead smelters-may be exposed to 10 times the average United States atmospheric levels of arsenic. The agency says that 40,000 people living near some copper smelters may be exposed to 100 times the national atmospheric average.
First aid
If this chemical gets into the eyes, remove any contact lenses at once and irrigate immediately for at least 15 minutes, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts the skin, remove contaminated clothing and wash immediately with soap and water. Seek medical attention immediately. If this chemical has been inhaled, remove from exposure, begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if heart action has stopped. Transfer promptly to a medical facility. When this chemical has been swallowed, get medical attention. Give large quantities of water and induce vomiting. Do not make an unconscious person vomit.
UN1558 Arsenic, Hazard Class: 6.1; Labels: 6.1-Poisonous materials.
Incompatible with strong acids; strong oxidizers; peroxides, bromine azide, bromine pentafluoride, bromine trifluoride; cesium acetylene carbide, chromium trioxide; nitrogen trichloride, silver nitrate. Can react vigorously with strong oxidizers (chlorine, dichromate, permanganate). Forms highly toxic fumes on contact with acids or active metals (iron, aluminum, zinc). Hydrogen gas can react with inorganic arsenic to form highly toxic arsine gas.
Waste Disposal
Elemental arsenic wastes should be placed in long-term storage or returned to suppliers or manufacturers for reprocessing. Arsenic pentaselenide-wastes should be placed in long-term storage or returned to suppliers or manufacturers for reprocessing. Arsenic trichloride: hydrolyze to arsenic trioxide utilizing scrubbers for hydrogen chloride abatement. The trioxide may then be placed in long-term storage. Arsenic trioxide: long-term storage in large shiftproof and weatherproof silos. This compound may also be dissolved, precipitated as the sulfide and returned to the suppliers. Arsenic-containing sewage may be decontaminated by pyrolusite treatment. Consult with environmental regulatory agencies for guidance on acceptable disposal practices. Generators of waste containing this contaminant (≥100 kg/mo) must conform with EPA regulations governing storage, transportation, treatment, and waste disposal. In accordance with 40CFR165, follow recommendations for the disposal of pesticides and pesticide containers. Must be disposed properly by following package label directions or by contacting your local or federal environmental control agency, or by contacting your regional EPA office.

Material Safety Data Sheet(MSDS)

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