potassium ferricyanide

chemical compound

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July 1, 2026

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Potassium ferricyanide, also known as red prussiate of potash, is a red crystalline salt with the chemical formula K₃Fe(CN)₆. It is produced by oxidizing potassium ferrocyanide with chlorine. This compound is primarily utilized as a photographic bleach and in the process of coating blueprint paper.1

Potassium ferrocyanide, or yellow prussiate of potash, is a yellow crystalline salt with the formula K₄Fe(CN)₆. It is derived from cyanogen compounds, which are by-products of coal carbonization, or by reacting potassium cyanide with ferrous salts. Its main application is in the creation of iron blue pigments.2

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blueprint
…of ferric ammonium citrate and potassium ferricyanide, which is then exposed to light. In the areas of the sensitized paper not obscured by the lines of the drawing, the light reduces the ferric salt to the ferrous state, in which it reacts with the potassium ferricyanide to form insoluble prussian…
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…of ferric ammonium citrate and potassium ferricyanide, which is then exposed to light. In the areas of the sensitized paper not obscured by the lines of the drawing, the light reduces the ferric salt to the ferrous state, in which it reacts with the potassium ferricyanide to form insoluble prussian…
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coordination compound
Characteristics of coordination compounds
…ions include potassium hexacyanoferrate(3−) (potassium ferricyanide), K₃[Fe(CN)₆], and the hexahydrate of nickel chloride, hexaaquanickel(2+) chloride, [Ni(H₂O)₆]Cl₂. In each case the charge on the complex ion is balanced by ions of opposite charge. In the case of potassium ferricyanide, three positively charged potassium ions, K⁺, balance the negative charge on…
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…ions include potassium hexacyanoferrate(3−) (potassium ferricyanide), K₃[Fe(CN)₆], and the hexahydrate of nickel chloride, hexaaquanickel(2+) chloride, [Ni(H₂O)₆]Cl₂. In each case the charge on the complex ion is balanced by ions of opposite charge. In the case of potassium ferricyanide, three positively charged potassium ions, K⁺, balance the negative charge on…
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