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Physical & Chemical properties

Water solubility

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Silicic acid, lithium magnesium sodium salt disperses in water to form a colloidal suspension rather than a solution. The colloidal suspension is totallyclear giving the appearance of a solution. This substance is insoluble in water, as demonstrated by dialysis at its natural pH in water of 9.8 and a temperature of 26 deg C

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This substance is an inorganic layered silicate structure with a unit cell of the following composition Na0.7+ [(Si8Mg5.5Li0.3) O20(OH)4]0.7- The material is non-biodegradable, retaining its clay structure in the environment. At normal water course pH’s this material is stable and insoluble. It does not dissolve in water but disperses to form a clear sol so the usual methods to determine water solubility do not work because it appears by observation that total dissolution has taken place whereas in reality the structure has remained unchanged but simply dispersed to be invisible to the naked eye. To demonstrate whether any solubility to the component ions takes place, adialysis method was devised to determine solubilised ions present. Based on the structureabove, lithium, sodium and magnesium were determined to be key identifiers of whether the structure under defined conditions dissociates in water. The natural pH of this substance in water at a concentration of 2% by weight is 9.8. At that pH, no free lithium or magnesium ionsare found in solution and only low level concentration of sodium ions which are present from dissociation of free sodium sulphate left over from the manufacturing process as a low level impurity.