A single teaspoon of Hydrosorbent Silica Gel has an internal "adsorptive" area equivalent to a football field, including the two end zones. How can Hydrosorbent Silica Gel Dehumidifiers be reused?. Silica gel was developed just prior to WWI and was used in Allied gas masks; then, in WWII it was used extensively to keep penicillin dry.
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