(Solved): (5) The precipitation and dissolution of \( \mathrm{CaCO}_{3} \) is one of the important solubility ...

(5) The precipitation and dissolution of \( \mathrm{CaCO}_{3} \) is one of the important solubility reactions in seawater. The reaction can be written as: \( \mathrm{CaCO}_{3}(\mathrm{~s})=\mathrm{Ca}^{2+}+\mathrm{CO}_{3}{ }^{2-} \) a) Calculate \( \Delta \mathrm{Gr} \) for this reaction given the following \( \Delta \mathrm{Gf} \) species b) Calculate the equilibrium constant for this solubility reaction at \( 25^{\circ} \mathrm{C} \). c) The surface water concentration of \( \left[\mathrm{CO}_{3}^{-}\right] \)is about \( 260 \mu \mathrm{M} \) and \( \mathrm{Ca}^{2+} \) is \( 10.28 \mathrm{mM} \). Is the water at saturation with respect to \( \mathrm{CaCO}_{3} \) ? (Use the Keq value calculated in part b) d) The deep water (at 4,500 meters in the Pacific) concentration of [CO3"] is about \( 80 \mu \mathrm{M} \). Is the deep water at saturation with respect to \( \mathrm{CaCO}_{3} \) ? (Use value of \( \mathrm{Keq} \) at \( 4^{\circ} \mathrm{C}=10^{-5.95} \) )