Silicate, soluble

Vitreous silica does not react significantly with water under ambient conditions. The solution process involves the formation of monosilicic acid, Si(OH)4. Solubility is fairly constant at low pH but increases rapidly when the pH exceeds 9 (84—86). Above a pH of 10.7 silica dissolves mainly as soluble silicates. Solubility also increases with higher temperatures and pressures. At 200—400°C and 1—30 MPa (<10"300 atm), for example, the solubility, S, of Si02 in g/kg H20 can be expressed as follows, where dis the density of the vapor phase and Tis the absolute temperature in Kelvin. 

SILICATES (Soluble). The most common and commercially used soluble silicates are those of sodium and potassium. Soluble silicates are systems containing varying proportions of an alkali metal or quaternary ammonium ion and silica. The soluble silicates can be produced over a wide range of stoichiometric and nonstoicluometric composition and are distinguished by the ratio of silica to alkali. This ratio is generally expressed as the weight percent ratio of silica to alkali-metal oxide (SiOj/MjO). Particularly with lithium and quaternary ammonium silicates, the molar ratio is used. 

Ammonium chloride or ammonium carbonate Silver nitrate Gelatinous precipitate Yellow precipitate of silver silicate soluble in dilute acids as well as ammonia solution... 

Barium chloride solution white precipitate of barium silicate, soluble in dilute nitric acid. 

Figure 1. Ash composition changes on route from mineral matter to boiler deposits insoluble silicates soluble silicates ...

Silica is converted into monosilicic acid by fusing with sodium carbonate and acidifying the alkaline solution produced when the melt is dissolved in water. Alternatively, an acidic sample solution may be made alkaline with sodium hydroxide and heated to convert colloidal silica into silicate. Soluble monosilicic acid is formed after appropriate dilution and acidification. 

Potassium Silicate, Soluble potash glass soluble... 

Aluminum silicate solubility in water, according to these reactions, may be calculated from equilibrium content of AP in the saturated solution in consideration of its complexation function 3+. Then the solubility equations of the minerals under consideration are... 

Synonyms Disodium metasilicate Disodium monosilicate Silicic acid, disodium salt Sodium metasilicate anhydrous Sodium silicate Soluble glass Water glass... 

Sodium vinyl sulfonate polymerized. See Polysodium vinyl sulfonate Solanum tuberosum. See Potato (Solanum tuberosum) starch Soluble glass. See Sodium metasilicate Sodium silicate Soluble guncotton. See Nitrocellulose Solum diatomeae. See Diatomaceous earth... 

Sodium silicate, Na SiOj is the only common silicate soluble in water. Most of the other silicates are insoluble due to the presence of the strong Si - 0 bond in silicates. 

Postcured silicates Soluble silicates are combined with zinc dust to form very hard rocklike films that are further stabilized by reacting them with an acidic curing agent. 

Fluoride indirect differential method Silicates, soluble... 

Solution pH may also have an indirect control on silicate solubility above the direct control offered by proton concentration in the proton-enhanced... 

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