Carbonates are among the most abundant and important minerals in the earth's crust. When these minerals come into contact with fresh water or seawater, solubility equilibria are established that greatly affect the chemistry of the natural waters. Calcium carbonate (CaCO3), the most important natural carbonate, makes up limestone and other forms of rocks, such as marble. Other carbonates include Dolomite (CaMg(CO3)2, and magnesite M9CO3. These compounds are sufficiently soluble that their solutions are nonideal, so calculations based on solubility equilibria are only approximations. a. The rare mineral nesquehonite contains MgCO3, together with hydration water (M9CO3.XH2O). A sample containing 21.7 g of nesquehonite is acidified and heated, and 3.51 L of CO2(g) at 0°C and 1 atm are produced. Assuming all the carbonate has reacted to form CO2(g), what is the chemical formula of nesquehonite? b. Write a chemical equation and the equilibrium constant (solubility product) expression for the dissolution of magnesite in water c. In a sufficiently basic solution, the carbonate ion does not react significantly with water to form hydrogen carbonate ion. Calculate the solubility (in grams per liter) of limestone (CaCO3) in a 0.092 M solution of sodium hydroxide. Ksp= 8.7x10-9 d. A similarly strongly basic solution is made with the limestone and 0.1 M of Na2CO3 yielding a concentration of CO32- of 0.1 M. What is the gram solubility of limestone in this solution? Compare your answer to the one from the previous problem. and provide an explanation. e. In a mountain lake having pH 8.7, the total concentrations of carbonate species [CO32] + [HCO3] = 9.6x10-4 М, whereas the concentration of Ca2+ is 8.3x10-4 Calculate the concentration of CO32- in this lake, using Ka=4.8 x10-11 for the acid ionization of HCO3 to CO32. Is the lake unsaturated, saturated or supersaturated with respect to CaCO3? f. Will acid rain rainfall into the lake increase or decrease the solubility of limestone rocks in the lake's bed? g. Seawater contains a high concentration of CI" ions, which form weak complexes with calcium, such as the ion pair [CaCl]. Does the presence of such complexes increases, decreases or maintains the same the equilibrium solubility of CACO3 in seawater? Justify your answer using 50 words or less.