In the last 100 years, the average global temperature has increased by approximately 0.8°C. If the atmospheric CO2 continues to increase at the current rates, the concentrations will reach 550 ppm by 2050. Such concentrations of atmospheric CO2 may result in irreversible environmental damages. Thus, the development of a successful method of CO2 storage is imperative. Injection of clean and compressed CO2 into geological reservoirs is recently the most explored method. This thesis reports the effect that CO2 has on the solubility of CaCO3, and vice versa. It addresses the thermodynamic conditions that may lead to CO2 storage via the formation of solid Ca(HCO3)2. The results obtained demonstrate that limestone increases the solubility of CO2 at low CO2 pressures and concentrations. It was also determined that the equilibrium pressure at which the reversible reaction between CaCO3 and Ca(HCO3)2 occurs is much lower than the previously speculated pressure of 15 atm.