Physicochemical properties solid agents

A colloid is a material that exists ia a finely dispersed state. It is usually a solid particle, but it may be a Hquid droplet or a gas bubble. Typically, coUoids have high surface-area-to-volume ratios, characteristic of matter ia the submicrometer-size range. Matter of this size, from approximately 100 nm to 5 nm, just above atomic dimensions, exhibits physicochemical properties that differ from those of both the constituent atoms or molecules and the macroscopic material. The differences ia composition, stmcture, and iateractions between the surface atoms or molecules and those on the iaterior of the colloidal particle lead to the unique character of finely divided material, specifics of which can be quite diverse (see Flocculating agents). 

Venkastewara Rao A, Nilsen E, Einarsrud MA (2001) Effect of precursOTs, methylation agents and solvents on the physicochemical properties of silica aerogels prepared by almospheric pressure drying method. J Non-Cryst Solids 296 165-171... 

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