Silica gel desiccant is the greatest deal of internal surface area which is the grate adsorbent from the other desiccants. These silica gel beads have micro-porous structure that has interlocking cavity that results in high surface area. These self-indicating gels are basically the same as normal indicators but with only the exception that in these gels, chemical or organic components are added that are sensitive to moisture. These chemicals react differently to the different levels of moisture. Their reaction is shown by their color change. Low vapor density is responsible for the fact that water is able to stay on the surface of the beads. The process of adsorption by these beads gets stopped when the state of equilibrium is attained. This state is basically reached when the air pressure of the surface and the surroundings gets equal.
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