Silica gel, in this form, refers to colloidal silica (also known as silica sol), a stable aqueous suspension of amorphous nano-sized silica particles (10-20 nm) with a concentration of 29-31%, pH 8.5-10, density 1.19-1.21 g/cm³, and low viscosity. As an analytical reagent (AR grade), it exhibits high purity, minimal soluble matter, and controlled loss on ignition. Colloidal silica is widely utilized in precision industries: as a polishing slurry for semiconductors, glass, and optical components; as a binder and rheology modifier in coatings, paints, adhesives, and refractories; in paper production to enhance drainage, retention, and surface strength; as a catalyst support or additive in chemical processes; and in water treatment for flocculation and clarification. Its nanoscale particles provide excellent colloidal stability, high surface area, and versatility in formulating advanced materials.