Hydrated glass

Soluble sodium sibcate glass sobd and bquid (anhydrous). Excludes quantities consumed in the manufacture of meta-, ortho-, and sesquisibcates. Includes quantities consumed in the manufacture of glass powder, hydrated glasses, and precipitated products. Shipment figures include unspecified amounts shipped to other plants for the manufacture of meta-, ortho-, or sesquisibcates. 

Figure 5.8 Model of hydrated glass surface showing the development of the hydrated layer. (Reprinted from Doremus, 1975 Figure 3. Copyright 1975 with permission from Elsevier.)...

A CFSE CFSE MgO - glass A120, - glass hydrate - glass... 

Hydrated glass, high dose rate O Dry glass, high dose rate A Hydrated glass, low dose rate A Dry glass, low dose rate... 

The equilibrium constant for this process is so large that the surface of a hydrated glass membrane ordinarily consists entirely of silicic acid (H Gl") groups. An exception to this situation exists in highly alkaline media, where the hydrogen ion concentration is extremely small and the sodium ion concentration is large here, a significant fraction of the sites are occupied by sodium ions. 

A fortiori, in hydrated glasses, all the water is intimately linked to the silicic polyanions. These results make it easier to raderstand the impact of water quantity on the properties of sodium silicates in aqueous solution or in the washing medium. 

Silicate solutions and hydrated glasses consist of a distribution of a large number of molecular species that cannot be isolated. It is clear that for most of the products, especially the amorphous ones, the measured detergent effects are due to a population of polymers, oligomers, and monomers. It is the variation in the distribution of this population that lends the silicates different detergent properties. 

Since the pH measurement is dependent on a hydrated glass bulb and a free-flowing junction from the reference electrode, keeping both electrodes wet is vital. 

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