As=74.9.

1. Acidum Arsenosum. Arsenous Acid

Acidum Arsenosum. Arsenous Acid. As2O3=197.68. Synonyms. - Arsenic Trioxide. White Arsenic

Source

Arsenical ores are roasted and purified by sublimation. Characters.-A heavy, solid, occurring either as an opaque, white powder, or in irregular masses of two varieties - the one amorphous, transparent and colorless, the other crystalline, opaque or white. Solubility. - In 30 to 80 parts of cold, in 15 parts of boiling water.

Incompatible

Lime water, iron salts, and magnesia.

Impurities

Lime salts.

Dose, 1/60 to 1/10 gr.; .001 to .006 gm.

Preparations

1. Liquor Potassii Arsenitis. Solution Of Potassium Arsenite

Liquor Potassii Arsenitis. Solution Of Potassium Arsenite. Synonym. - Fowler's solution. Arsenous Acid, 10; Potassium Bicarbonate, 20; Compound Tincture of Lavender, 30. Boil in sufficient distilled water to make 1000. No decomposition occurs, but an alkaline solution of arsenous acid is formed. Strength. - 1 per cent. of Arsenous Acid.

Dose, 2 to 10 m.; .12 to .60 c.c.

2. Liquor Acidi Arsenosi. Solution Of Arsenous Acid

Liquor Acidi Arsenosi. Solution Of Arsenous Acid. Arsenous Acid, 10; is boiled with diluted Hydrochloric Acid, 50; and distilled water to make 1000. No decomposition occurs, but an acid solution of arsenous acid is formed. Strength. - 1 per cent. of Arsenous Acid.

Dose, 5 to 10 m.; .30 to .60 c.c.

2. Sodii Arsenas. Sodium Arsenate

Sodii Arsenas. Sodium Arsenate. Na2HAsO4+7H2O= 311.46.

Source

Heat to redness Arsenous Acid, Sodium Nitrate, and Sodium Carbonate; dissolve the fused mass in water and crystallize. Sodium Pyro-arsenate is formed. As2O3+2NaNo3+Na2Co3=Na4As2O7+N2O3+Co2 On adding water to the Pyroarsenate, a solution of Sodium Arsenate, which crystallizes on standing, is formed. Na4As2O7+H2O=2Na2HAsO4, which crystallizes with 7H2O.

Characters

Colorless, transparent, monoclinic prisms, having a mild alkaline taste. Solubility. - In 4 parts of water.

Dose, 1/10 to 1/10 gr.; .002 to .006 gm.

Preparation

Liquor Sodii Arsenatis

Solution of Sodium Arsenate. Synonym. - Pearson's solution. (Pearson's solution is really one-fifth as strong as the official Liquor Sodii Arsenatis.)

Source

Dissolve Sodium Arsenate, 1; deprived of its water of crystallization by heat, in distilled water, 100. Strength. - 1 per cent of Sodium Arsenate.

Dose, 1 to 10 m.; .06 to .60 c.c.

3. Arseni Iodidum. Arsenic Iodide

Arseni Iodidum. Arsenic Iodide. AsI3=454.49. Source. - Made by the direct union of Iodine and Metallic Arsenic or by mixing solutions of Arsenous and Hydriodic Acids and evaporating.

Characters

Glossy orange-red, crystalline masses, or shining orange-red, crystalline scales, having an Iodine-like odor or taste. Solubility. - In 7 parts of water, and in 30 parts of Alcohol.

Dose, 1/30 to 1/10 gr.; .002 to .006 gm.

Preparation. Liquor Arseni et Hydrargyri Iodidi. See Mercury, p. 212.

4. Ferri Arsenas. See Iron, p. 196.