Iron nitrate - Shousan Tetsu

[ I ] Iron(II) nitrate: Fe(NO ₃ ) ₂ ･6H ₂ O (278.95). No anhydride has been obtained. It precipitates when iron(II) sulfide or iron is dissolved in cold dilute nitric acid (density 1.034 g cm ^-3 or less). Inorganic to pale green plate-like crystals. Melting point 60.5 °C. Easily soluble in water. Aqueous solution is acidic. [CAS 14013-86-6: Fe(NO ₃ ) ₂ ][CAS 13476-08-9: Fe(NO ₃ ) ₂ ･6H ₂ O] [ II ] Iron(III) nitrate: Fe(NO ₃ ) ₃ ･9H ₂ O (404.00). No anhydride has been obtained. It precipitates when iron powder is dissolved in 20-30% nitric acid and cooled. Inorganic to pale purple crystals. Density: 1.68 g cm ^-3 . Melting point: 47.2 °C. When melted, it becomes a red liquid and decomposes at 125 °C. Adding anhydrous nitric acid to the molten nonahydrate and cooling it gives the hexahydrate. Fe( _NO3 ) ₃ ･ _6H2O is a colorless crystal with a melting point of 35 °C. Both are highly deliquescent. Easily soluble in water. The aqueous solution is acidic and will hydrolyze over time to turn brown. The aqueous solution decomposes into iron(II) nitrate and oxygen when exposed to ultraviolet light. Soluble in ethanol and acetone, slightly soluble in nitric acid. As a strong oxidizing agent, there is a risk of fire if it is left in contact with organic matter. Used in catalysts, metal surface treatment agents, mordants, leather tanning agents, pharmaceuticals, and pigment manufacturing. [CAS 7782-61-8]

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

【Ⅰ】硝酸鉄(Ⅱ)：Fe(NO₃)₂･6H₂O(278.95)．無水物は得られていない．硫化鉄(Ⅱ)または鉄を，冷希硝酸(密度1.034 g cm^－3 以下)に溶かすと析出する．無～淡緑色の板状晶．融点60.5 ℃．水に易溶．水溶液は酸性を示す．[CAS 14013-86-6:Fe(NO₃)₂][CAS 13476-08-9:Fe(NO₃)₂･6H₂O]【Ⅱ】硝酸鉄(Ⅲ)：Fe(NO₃)₃･9H₂O(404.00)．無水物は得られていない．鉄粉を20～30％ 硝酸に溶かして冷却すると析出する．無～淡紫色の結晶．密度1.68 g cm^－3．融点47.2 ℃．溶融すると赤色の液体になり125 ℃ で分解する．融解した九水和物に無水硝酸を加えて冷却すると六水和物が得られる．Fe(NO₃)₃･6H₂Oは無色の結晶で，融点35 ℃．いずれも潮解性が強い．水に易溶．水溶液は酸性を呈し，時間が経つと加水分解して褐色になる．水溶液は紫外線により硝酸鉄(Ⅱ)と酸素に分解する．エタノール，アセトンに可溶，硝酸に微溶．強酸化剤なので有機物に接触させておくと発火する危険がある．触媒，金属表面処理剤，媒染剤，皮なめし剤，医薬品，顔料製造などに用いられる．[CAS 7782-61-8]

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