Arsenic solution , analyticalstandard,100mg/LinH2SO4 , 7440-38-2
Synonym(s):
Arsenic black;Arsenic-75;AS006125
CAS NO.：7440-38-2
Empirical Formula: AsH3
Molecular Weight: 77.95
MDL number: MFCD00085309
EINECS: 231-148-6
PRODUCT Properties
| Melting point: | 817 °C(lit.) |
| Boiling point: | 613 °C(lit.) |
| Density | 5.727 g/mL at 25 °C(lit.) |
| vapor pressure | 1Pa at 280℃ |
| solubility | insoluble in H2O |
| form | powder |
| color | Silver to black |
| Specific Gravity | 5.727 |
| Odor | Odourless |
| Resistivity | 33.3 μΩ-cm |
| Water Solubility | insoluble |
| Sensitive | Air Sensitive |
| Merck | 13,802 |
| Exposure limits | TLV-TWA 0.2 mg(As)/m3 (ACGIH), 0.5 mg
(As)/m3 (MSHA), 0.01 mg(As)m3 (OSHA);
ceiling 0.002 mg(As)/m3/15 min (NIOSH);
carcinogenicity: Human Sufficient Evidence
(IARC). |
| Stability: | Stable. Incompatible with acids, oxidizing agents, halogens. Heat and air-sensitive. |
Description and Uses
Arsenic is a metalloid of the nitrogen group. Two allotrope forms of elemental arsenic have been reported: yellow arsenic and grey arsenic, the latter being usually the more stable form. Arsenic readily oxidises in air to arsenic trioxide (As2O3). Arsenic is mostly found either in its native state or as arsenic sulfide in the form of realgar (As4S4) or orpiment (As2S3). Arsenic can exist in three different valence states (zerovalent, trivalent and pentavalent). Arsenic forms covalent bonds with carbon, oxygen and hydrogen. The toxicity varies widely and depends on the physical state of the compound and its absorption/elimination rate. Trivalent arsenics (As(III)) are derivatives of the arsenous acid (H2AsO3-arsenite) and arsenic trioxide (AsO3). Examples of pentavalent arsenic (As(V)) include derivatives of the arsenic acid (H3AsO4 -arsenate). Organic arsenic-based compounds, that is, compounds containing arsenic-carbon bonds, are usually less toxic than their inorganic counterparts. This is mainly due to their quicker excretion from the human body. Arsenic is known to be one of the most toxic heavy metals. Compounds containing arsenic have a long history of use as poisons, but they also have a long historical medicinal use.
Inorganic arsenic compounds were widely used as pesticides from the mid 1800s to the mid 1900s and were used in medicine until the 1970s, primarily for treatment of leukemia, psoriasis, and asthma. The use of arsenic for treatment of acute promyelocytic leukemia resumed in the 1990s. By the mid 1970s, arsenic use was shifting from pesticides to wood preservatives, and by 1980, wood preservatives were the primary use. Total agricultural-chemical use (in pesticides and fertilizers) declined to about 15% to 20% of total arsenic consumption by the early 1990s and has remained at about 4% since 1995 (Edelstein 1994, Reese 1998, ATSDR 2007, Brooks 2009).
Since the mid 1990s, arsenic trioxide used in wood preservation has accounted for 86% to 90% of total U.S. arsenic consumption. Wood treated with chromated copper arsenate (CCA), known as “pressure-treated wood,” has been used widely to protect utility poles, building lumber, and foundations from decay and insect attack. However, a voluntary phase-out of CCA for certain residential uses (e.g., in wood for decks, play structures, fencing, and boardwalks) that went into effect December 31, 2003, has reduced this use of arsenic. CCA continues to be used in wood products for industrial use. Other uses of arsenic in the 1990s included use in glass (3% to 4%) and nonferrous alloys (1% to 4%) (ATSDR 2007, Brooks 2009).
By the 1990s, there was renewed interest in the use of arsenic for treatment of acute promyelocytic leukemia (ATSDR 2007). Arsenic trioxide is approved by the U.S. Food and Drug Administration for treating this type of leukemia when other chemotherapy treatments have failed (MedlinePlus 2009). Arsenic is also used in the production of lead alloys used in lead-acid batteries. It may be added to alloys used for bearings, type metals, lead ammunition, and automotive body solder, and it may be added to brass to improve corrosion resistance. High-purity arsenic is used in a variety of semiconductor applications, including solar cells, light-emitting diodes, lasers, and integrated circuits (ATSDR 2007).
Safety
| Symbol(GHS) |     GHS05,GHS06,GHS08,GHS09 |
| Signal word | Danger |
| Hazard statements | H301+H331-H315-H318-H350-H410 |
| Precautionary statements | P273-P280-P301+P310-P302+P352-P304+P340+P311-P305+P351+P338 |
| Hazard Codes | T,N |
| Risk Statements | 23/25-50/53-36/38-22-45-52/53-51/53 |
| Safety Statements | 20/21-28-45-60-61-26-53 |
| OEL | Ceiling: 0.002 mg/m3 [15-minute] |
| RIDADR | UN 1558 6.1/PG 2 |
| WGK Germany | 3 |
| RTECS | CG0525000 |
| F | 10 |
| TSCA | Yes |
| HazardClass | 6.1 |
| PackingGroup | II |
| HS Code | 28048000 |
| Toxicity | Human exposure occurs occupationally and via food, tobacco smoke, ambient air, and water. Three major groups of arsenic compounds have been defined on the basis of biological considerations: inorganic arsenicals; organic arsenicals; and arsine (gas). The comparative toxicity of these groups is dependent upon the route of exposure and their solubilities; the more quickly absorbed compounds have lower LD50. Arsenic is readily absorbed by the respiratory and gastrointestinal systems and is concentrated in the skin, hair, and nails (Aldrich-Mees’ lines). The cellular toxicity of arsenic is related to reactions with SH-containing mitochondrial enzymes that result in impaired respiration. Arsenic may also compete with phosphate during oxidative phosphorylation. |
| IDLA | 5 mg As/m3 |
