Prussian Blue (color) - Production

Production

Prussian blue is produced by oxidation of ferrous ferrocyanide salts. These white solids have the formula M2Fe where M+ = Na+ or K+. The iron in this material is all ferrous, hence the absence of deep color associated with the mixed valency. Oxidation of this white solid with hydrogen peroxide or sodium chlorate produces ferricyanide and affords Prussian Blue.

A "soluble" form of PB, K, which is really colloidal, can be made from potassium ferrocyanide and iron(III):

K+ + Fe3+ + 4- → KFeIII

The similar reaction of potassium ferricyanide and iron(II) results in the same colloidal solution, because 3- is converted into ferrocyanide.

"Insoluble" Prussian blue is produced if in the reactions above an excess of Fe3+ or Fe2+, respectively, is added. In the first case:

4Fe3+ + 34- → FeIII3

Read more about this topic:  Prussian Blue (color)

Famous quotes containing the word production:

    It is part of the educator’s responsibility to see equally to two things: First, that the problem grows out of the conditions of the experience being had in the present, and that it is within the range of the capacity of students; and, secondly, that it is such that it arouses in the learner an active quest for information and for production of new ideas. The new facts and new ideas thus obtained become the ground for further experiences in which new problems are presented.
    John Dewey (1859–1952)

    ... if the production of any commodity necessitates the sacrifice of human life, society should do without that commodity, but it can not do without that life.
    Emma Goldman (1869–1940)

    Constant revolutionizing of production ... distinguish the bourgeois epoch from all earlier ones. All fixed, fast-frozen relations, with their train of ancient and venerable prejudices are swept away, all new-formed ones become antiquated before they can ossify. All that is solid melts into air, all that is holy is profaned, and man is at last compelled to face with sober senses, his real conditions of life, and his relations with his kind.
    Karl Marx (1818–1883)