Calcium ferrate

Other ferrate salts include calcium ferrate [35764-67-1], and sodium ferrate [13773-03-0]. The magnetic moments of these materials are 2.63.0 X 10 J/T (2.8-3.2 ), which is consistent with the expectation of two unpaired electrons. The [FeOJ ion is an extremely strong oxidizing... 

Ca2Fe20s (s) 2CaO Fe203 (s) Calcium Ferrate(lll) Ca2Fe20s (s) 2CsO F62O3 (s)... 

FTIR spectra of calcium ferrate (VI), CaFe04. Spectra were measured by a Nicolet Nexus 670 Fourier transform infrared spectrophotometer in a conventional KBr pellet. (Adapted from Ref. 78 with permission of Elsevier.)... 

Heating with the following solids, their fusions, or vapours (a) oxides, peroxides, hydroxides, nitrates, nitrites, sulphides, cyanides, hexacyano-ferrate(III), and hexacyanoferrate(II) of the alkali and alkaline-earth metals (except oxides and hydroxides of calcium and strontium) (b) molten lead, silver, copper, zinc, bismuth, tin, or gold, or mixtures which form these metals upon reduction (c) phosphorus, arsenic, antimony, or silicon, or mixtures which form these elements upon reduction, particularly phosphates, arsenates,... 

Strontium perferrate, SrFe04, is obtained 4 by double decomposition of the potassium salt and a saturated, neutral solution of strontium bromide. The precipitate is washed with alcohol and ether. Obtained in this manner, the strontium ferrate is not pure, but contains admixed ferric oxide. It is deep red in colour, slightly soluble in water, and readily decomposed by acids. It is useful for preparing aqueous solutions 4 of the perferrates of the less common alkali metals—lithium, rubidium, caesium—of calcium and magnesium. 

Portland cement, a complex mixture of calcium silicates, aluminates, and ferrates, is one of the world s most important construction materials, with annual worldwide production in excess of lO kg. When mixed with water and sand, it changes by slow hydration to concrete. Water and hydroxide link the other components into larger crystals with great strength. 

Neutralising value is an analytical term for that proportion of limestone, quicklime, or hydrated lime (expressed as CaO) that is capable of reacting with hydrochloric acid under specified conditions. It includes the contribution of CaCOs, CaO, Ca(OH)2, and the acid-soluble fraction of the calcium silicates, aluminates and ferrate. 

Ordinary Portland cement is a controlled blend of calcium silicates, aluminates and ferrate, which is ground to a fine powder with gypsum and other materials (see chapter 9). 

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