Copper hydroxide - Suisankado

[ I ] Copper(I) hydroxide: CuOH (80.55). When an alkali hydroxide is added to an aqueous solution of copper(I) salt, a yellow precipitate is obtained. The product is said to be copper(I) hydroxide, but it is more likely to be Cu ₂ O･(H ₂ O) _n or Cu ₂ O. The yellow color is said to be due to the size of the precipitate particles. At 360 °C, it dehydrates and becomes copper(I) oxide. Also, if the precipitate is boiled in water, it becomes red copper(I) oxide. [ II ] Copper(II) hydroxide: Cu(OH) ₂ (97.57). When a small excess of an alkali hydroxide is added to an aqueous solution of soluble copper(II) salt and kept at 0 °C, a blue gel-like copper(II) hydroxide is obtained. Density 2.36 g cm ^-3 . The gel-like substance is highly reactive. When heated to 60-80 °C, it turns into black copper(II) oxide. It has somewhat amphoteric properties and dissolves in concentrated alkali as [Cu(OH) ₄ ] ^2- . It does not dissolve in dilute acids. It dissolves in aqueous ammonia and potassium cyanide solution forming a complex salt. The tetraammine complex [Cu(NH ₃ ) ₄ ](OH) ₂ solution is deep blue and is used in the qualitative analysis of copper. It is also used as Schweitzer's reagent to dissolve cellulose. It is also used as a mordant, pigment, in the manufacture of copper salts, as a catalyst raw material, and in colored paper. [CAS 20427-59-2]

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

【Ⅰ】水酸化銅(Ⅰ)：CuOH(80.55)．銅(Ⅰ)塩水溶液に水酸化アルカリを加えると黄色の沈殿として得られる．生じたものは水酸化銅(Ⅰ)とされているが，それよりはCu₂O･(H₂O)_nかCu₂Oであろうといわれている．黄色は沈殿の粒の大きさによるとされている．360 ℃ で脱水，酸化銅(Ⅰ)になる．また，沈殿を水中で煮沸すると赤色の酸化銅(Ⅰ)になる．【Ⅱ】水酸化銅(Ⅱ)：Cu(OH)₂(97.57)．可溶性銅(Ⅱ)塩水溶液に小過剰の水酸化アルカリを加えて0 ℃ に保つと，青色のゲル状の水酸化銅(Ⅱ)が得られる．密度2.36 g cm^－3．ゲル状のものは反応性が強い．60～80 ℃ に加熱すると黒色の酸化銅(Ⅱ)にかわる．いくぶん両性の性質をもち，濃アルカリには [Cu(OH)₄]^2－ となって溶ける．希薄な酸には溶けない．アンモニア水，シアン化カリウム水溶液には錯塩をつくって溶ける．テトラアンミン錯体[Cu(NH₃)₄](OH)₂溶液は濃青色で，銅の定性分析に利用される．また，シュワイツァー試薬としてセルロースの溶解にも用いられる．そのほか，媒染剤，顔料，銅塩の製造，触媒原料，着色紙などに用いられる．[CAS 20427-59-2]

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