Ferricyanide sentence example
- They combine readily with the alkyl iodides to form alkyl acridinium iodides, which are readily transformed by the action of alkaline potassium ferricyanide to N-alkyl acridones.
- Potassium ferricyanide, K 3 Fe(NC)s, red prussiate of potash, is obtained by oxidizing potassium ferrocyanide with chlorine, bromine, &c., 2K 4 Fe(NC) 6 + C1 2 = 2K 3 Fe(NC) 6 + 2KC1.
- With silver nitrate it gives an orange red precipitate of silver ferricyanide, Ag 3 Fe(NC)s.
- Turnbull's blue, Fe5(NC)12 or Fe3[Fe(NC)6]2, ferrous ferricyanide, is best obtained by adding a hot solution of potassium ferricyanide to a ferrous salt, and allowing the mixture to stand some time in the presence of an iron salt: 2K 3 Fe(NC)s+3FeSO 4 = Fe3[Fe(NC)s]z+ 3K 2 SO 4.
- Hydroferricyanic acid, H 3 Fe(NC)s, obtained by adding concentrated hydrochloric acid to a cold saturated solution of potassium ferricyanide, crystallizes in brown needles, and is easily decomposed.Advertisement
- It may be recognized by the violet coloration it gives when added to a very dilute solution of potassium bichromate in the presence of hydrochloric acid; by the orange-red colour it gives with a solution of titanium dioxide in concentrated sulphuric acid; and by the precipitate of Prussian blue formed when it is added to a solution containing ferric chloride and potassium ferricyanide.
- Alkaline potassium ferricyanide oxidizes it to picric acid.
- With potassium bichromate solution, which is yellow, the iron solution becomes green from the chromium chloride or sulphate formed, and the end of the reaction is determined by removing a drop of the solution on the stirring-rod and adding it to a drop of a dilute solution of potassium ferricyanide on a white tile.
- Senderens, Comptes rendus, 1901, 132, p. 210 seq.); and from hydrazines of the type CnH2,2_1 NH NH2 by oxidation with alkaline potassium ferricyanide (N.
- A convenient way of conducting the test is to use paper impregnated with potassium ferricyanide.Advertisement
- Oxidizing agents (Cl, Br, H202, &c.) convert it into potassium ferricyanide (see below), a similar result being attained by the electrolysis of its aqueous solution: 2K 4 Fe(NC)s + 2H 2 0 = 2KOH + H2 + 2K 3 Fe(NC) 6.
- Chem., 1866, 9 8, p. 340); by the action of chlorine on steam at a bright red heat; by the decomposition of hydrogen peroxide by bleaching powder, manganese dioxide, potassium ferricyanide in alkaline solution, or potassium permanganate in acid solution; by heating barium peroxide with an aqueous solution of potassium ferricyanide (G.
- In the second group, we may notice the application of litmus, methyl orange or phenolphthalein in alkalimetry, when the acid or alkaline character of the solution commands the colour which it exhibits; starch paste, which forms a blue compound with free iodine in iodometry; potassium chromate, which forms red silver chromate after all the hydrochloric acid is precipitated in solutions of chlorides; and in the estimation of ferric compounds by potassium bichromate, the indicator, potassium ferricyanide, is placed in drops on a porcelain plate, and the end of the reaction is shown by the absence of a blue coloration when a drop of the test solution is brought into contact with it.
- Potassium ferrocyanide may be estimated quantitatively in acid solution by oxidation to ferricyanide by potassium permanganate (in absence of other reducing agents): 5K 4 Fe(NC)s + KMnO 4 + 4H2S04= 5K 3 Fe(NC)s + 3K2S04+MnS04+4H20.