Adsorption vs absorption
Surface Chemistry and Colloids · Chemistry
Study notes
Why does a silica gel packet keep a shoebox dry — adsorption or absorption? Step 1: Water molecules stick to silica's huge internal surface — surface phenomenon. Step 2: They do NOT dissolve into the silica bulk. Step 3: Hence adsorption (surface), not absorption (bulk). Step 4: Heating drives water off — the gel is reusable. Contrast: a sponge absorbs water into its pores (bulk).