酸化銀(Ⅰ) 化学特性,用途語,生産方法
外観
黒褐色の粉末
定義
本品は、銀(*)の酸化物であり、次の化学式で表される。
参照表示名称：銀
溶解性
硝酸に溶けやすく、水にほとんど溶けない。
解説
酸化銀(Ⅰ)，硝酸銀の濃水溶液に水酸化ナトリウムの希水溶液を加えて得られる暗褐色粉末。熱および光に対して不安定で、熱すると約160℃で分解し始め、250～300℃で急激に分解して酸素を放ち金属銀となる。水にわずかに溶け（水100gに0.00214g溶ける）、エタノール（エチルアルコール）に不溶。希硝酸、アンモニア水に溶ける。水溶液は強いアルカリ性で、空気中から二酸化炭素を吸収する。株式会社平凡社 世界大百科事典 第２版について 情報
用途
触媒、有機合成における脱ハロゲン剤。
化粧品の成分用途
殺菌剤
使用上の注意
光によって徐々に分解する。
化学的特性
Silver(I) oxide, Ag2O, is made by action of oxygen under pressure on silver at 300 °C, or by precipitation of a silver salt with carbonate-free alkali metal hydroxide; it is covalent, each silver atom (in solid Ag2O) having two collinear bonds and each oxygen atom four tetrahedral ones; two such interpenetrating lattices constitute the structure.
物理的性質
Brownish-black cubic crystals; density 7.14 g/cm
3 at 16°C; begins to decompose around 200°C, decomposition becoming rapid at 250 to 300°C; insoluble in water and ethanol; soluble in acids and alkalis; sparingly soluble in solutions of caustic alkalis; insoluble in alcohol.
使用
Polishing glass, coloring glass yellow, catalyst, purifying drinking water, lab reagent, carbon dioxide scrubber, and chemical sensors. It is used in the preparation of other silver compounds, and silver-oxide batteries. In organic chemistry, silver oxide finds use as an oxidizing agent for aldehyes to produce carboxylic acids.
製造方法
Silver(I) oxide is precipitated by mixing solutions of silver nitrate and caustic soda: 2AgNO
3 + 2NaOH → Ag2O + 2NaNO
3 + H
2O.
一般的な説明
Odorless brown-black solid. Sinks in water.
反応プロフィール
Hydrogen sulfide is rapidly oxidized and may ignite in contact with Silver oxide [Bretherick 1979 p. 977]; Mixtures of metal sulfides, gold(III) sulfide, antimony sulfide or mercury (II) sulfide, phosphorus, sulfur, selenium, and selenium disulfide ignite on grinding with the oxide. Ammonia or hydrazine slowly react with Silver oxide forming silver nitride or in the presence of alcohol, silver fulminate may also be produced [Bretherick 1979 p. 203]. Oxidation of magnesium is explosive when warmed with Silver oxide.
危険性
Fire and explosion risk in contact with
organic materials or ammonia.
健康ハザード
Contact with eyes causes mild irritation. If continued for a long period, ingestion or inhalation of silver compounds can cause permanent discoloration of the skin (argyria).
火災危険
Behavior in Fire: Decomposes into metallic silver and oxygen. If large quantities are involved, the oxygen might increase the intensity of the fire.
安全性プロファイル
A poison by intraperitoneal route. Moderately toxic by ingestion. Flammable by chemical reaction; an oxidizing agent. Explodes in contact with ammonia. Incompatible with CuO, (NH3 + ethanol), (hydrazine + ethanol), CO, HzS, Mg, auric sulfide, Sb sulfide, Hg sulfide, nitroalkanes, Se, S, P, K, Na, NaK, seleninyl chloride. See also SILVER COMPOUNDS.
純化方法
Leach the oxide with hot water in a Soxhlet apparatus for several hours to remove any entrained electrolytes. [Glemser & Sauer in Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol II p 1037 1965.]
酸化銀(Ⅰ) 上流と下流の製品情報
原材料
準備製品