The water–silicas interfacial interaction energies

The water–silicas interfacial interaction energies were calculated for samples of quartz, silicas and silicas outgassed at high temperatures using own and published data of the spreading pressure of water, its surface tension, its contact angle and using formulas obtained by the combination of the Young equation with a general equation of pair interaction. The values obtained for 18 different samples were in the range 7.80–6.92 kJ mol 1. Lower values of energies are for samples that contain relatively less amounts of water at P/P0 = 0.25 and are characterized also by relatively low values of surface pressures