Silicate general formula

Commercial soluble silicates have the general formula... 

Tacke et al. have reported a new family of spirocyclic silicates adopting betaine-type structures of the general formula X4SiCH2NR2H (X = electronegative atoms or groups R = organic groups) in which the silicon atoms are... 

The pyroxenes are chemically complex but common rock-forming minerals. They resemble the amphiboles in many ways, but are actually single-chain silicates. The tetrahedral basic unit of the pyroxenes, [(Al,Si)20g] , was schematically depicted in Fig. 2.1C. The general formula for the group is Ai (B, C)i+ TjOfi, where A = Ca" Fe Li+, Mg "", Na-" B = Mg ", Fe Mn" Sc+ C = Fe A Cr" Ti " and T = Si Al+l Within the group are several mineral series and several species that often occur in acicular or fibrous forms. One species that occurs in fibrous form is jadeite, [Na(Al,Fe )Si206], a relatively familiar name because of the popularity of this material with Oriental sculptors. 

The chlorites are a group of sheet silicate minerals similar to the micas and talc. The general formula, A5 6T40io(OH) j, is deceptively simple. The range of possible substitutions is enormous, for example, A = Mg, Al, Fe, ... 

HORNBLENDE. The mineral hornblende is a complex silicate. It is probably an isoinorphous mixture of three molecules, a calcium-iron-magnesium silicate, an aluminum-irou-magnesium silicate and an iron-magnesium silicate. A general formula ts... 

Silica gel is a polymer of silicic acid and has the general formula Si02 x H20. There are many ways to prepare silica gel. Let us consider only one preparation of silica gel to demonstrate how and where differences or variations in the silica may contribute to a different bonded (final) phase. A common way of making silica gel particles for LC is to use acidic hydrolysis of sodium silicate, followed by polycondensation dehydration of orthosilicic acid and grinding of the silica to make granular particles (e.g., 10 jam). If the reaction is not controlled (buffer, pH, temperature, etc.) the hydrogel will... 

The two main types of infinite chain anions are the pyroxenes, which contain singlestrand chains of composition (SiO ) (Fig. 8-4) and the amphiboles, which contain double-strand, cross-linked chains or bands of composition (SLOif),. Note that the general formula of the anion in a pyroxene is the same as in a silicate with a cyclic anion. Silicates with this general stoichiometry are often called metasilicates, especially in older literature. There is actually neither metasilidc add nor any discrete metasilicate anion. With the exception of the few metasilicates with cyclic anions, such compounds contain infinite chain anions. 

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