This powder is used often in Column Chromatography as the stationary phase. It is mixed together with the solvent in the column making a slurry, then letting the solvent drain leaving the Silica sitting evenly in the column. Silica Gel helps space out or separate the fractions of compounds being passed through the stationary phase. Pore Radius: 60A, Pore Volume: 0.5-0.7 m/g, Surface Area: 450-600 / g, Bulk Density: 500-600 g/l