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Interaction of freshly precipitated silica gel with aqueous solutions was studied at laboratory batch experiments under ambient and near neutral pH-conditions. The overall process showed excellent reversibility: gel growth could be considered as an opposite process to dissolution and a linear rate law could be applied to experimental data. Depending on the used rate law form, the resulting rate constants were sensitive to errors in parameters/variables such as gel surface area, equilibrium constants, Si-fluxes, and reaction quotients. The application of an Integrated Exponential Model appeared to be the best approach for dissolution data evaluation. It yielded the rate constants k dissol * (4.50 ± 0.68) 9 10 -12 and k growth * (2.58 ± 0.39) 9 10 -9 mol m -2 s -1 for zero ionic strength. In contrast, a Differential Model gave best results for growth data modeling. It yielded the rate constants k dissol * (1.14 ± 0.44) 9 10 -11 and k growth * (6.08 ± 2.37) 9 10 -9 mol m -2 s -1 for higher ionic strength (I * 0.04 to 0.11 mol L -1 ). The found silica gel solubility at zero ionic strength was somewhat lower than the generally accepted value. Based on the 298 K ðI¼0Þ SS ¼ 10 À2:754AE0:017 and 298 K ðI¼0Þ DBP ¼ 10 À2:728AE0:003 ; standard Gibbs free energy of silica gel formation was calculated as DG 0 f ð298 KÞ$ À 850,463 AE 98 J mol À1 and -850,318 ± 20 J mol -1 , respectively. Activation energies for silica gel dissolution and growth were determined as E dissol A $62:0 AE 3:2 kJ mol À1 and E growth A $48:8 AE 4:4 kJ mol À1 ; respectively. An universal value for growth of any silica polymorph, E growth A $37:4 AE 9:4 kJ mol À1 ; is not consistent with the value for silica gel growth, which questions the hypothesis about one unique activated complex controlling the silica polymorph growth.