Carbonates solubility-product constant

If S moles of CaCC>3 dissolve in a liter of water, then S moles each of calcium ion and carbonate ion form. With these ion concentrations equal to S, the solubility of CaCC>3 is calculated as 9.3 x 10 5 M. The higher solubility of magnesium carbonate in water, 6.3 x 10 3 M, results from the larger solubility product constant. Nevertheless, both of these carbonate salts are rather insoluble, and the excess carbonate anions provided by the sodium carbonate effectively precipitate the calcium and magnesium ions from solution. 

Total salinity based on K2 (second ionization constant for carbonic acid) and Kj (solubility product constant for CaCC>3) (in practice measured as total dissolved solids)... 

Note that the solubility product constant expression is true only when there is undissolved, solid material still present in the system. In other words, we are talking about (in this case) solid calcium carbonate in equilibrium with a saturated solution of calcium carbonate. 

Calcium hardness may either be carbonate or noncarbonate. The solubility product constant of CaC03 is K p = [Ca ][C03 ] = 5(10 ) at 25°C. A low value of the K p means that the snbstance has a low solnbility a valne of 5(10 ) is very low. Because of this very low solubility, calcium hardness is removed throngh precipitation of CaCOs. Becanse there are two types of calcinm hardness, there corresponds two general methods of removing it. When calcinm is associated with the bicarbonate ion, the hardness metal ion can be easily removed by providing the hydroxide radical. The of the bicarbonate becomes neutralized by the OH provided forming water and the ion necessary to precipitate calcinm carbonate. The softening reaction is as follows ... 

Let us digress for a moment from our discussion of the saturation pH in order to find the dead end cation for the carbonate system equilibria. Several of these cations can possibly pair with the carbonate. The pairing will be governed by the value of the solubility product constant, A small value of the means that only small values of the concentration of the constituent species are needed to form a product equal to the This, in turn, means that solids with smaller will easily form the solids. Thus, of all the possible cations that can pair with the carbonate, the one with the smallest K, value is the one that can form a dead end for the carbonate equilibria reactions. Mg forms MgCOs with a K,p of 10. Ca forms CaCOs with a K,p of 4.8(10 ). Table 11.3 shows other carbonate solids with the respective solubility product constants. 

Calculate the solubility product constant for calcium carbonate, given that it has a solubility of 5.3 X 10 g/L of water. 

You have been given the solubility product constant for CuCOj. The copper and carbonate Ion concentrations are in a one-to-one relationship with the molar solubility of CUCO3. Use the solubility product constant expression to solve for the solubility. Because K p is of the order of 10 °, you can predict that the solubility will be the square root of K p, or about 10 . ... 

Fe, Mn and Zn, which are more sensitive to pH and redox changes and have low solubility product constants as compared to Cu and Ni (42) appeared to have maintained strong intra-species positive correlations (Table III). On the other hand, Cu and Ni were observed to have behaved differently in the SRP aquatic systems as they did not show intra-species positive correlations. The dissolved (filterable) species of these elements (Cu and Ni) in the water systems were conceived to have acted independently from the rest of their species-exchangeable, carbonate, oxide and organic. 

The solubility product constant, K p, for calcium carbonate at room temperature is approximately 3.0 X 10 . Calculate the solubility of CaCOj in grams per liter under these conditions. 

The chemistry of Pb in natural systems is immensely complex. The solubility product constant (/fsp) of lead carbonate, hydroxide, phosphate, sulfide, and sulfate is 10, 10 10 10 , and... 

What is the average concentration of Pb in the earth s crust List the solubility product constant for lead carbonate, hydroxide, and sulfide. Which form is the least soluble ... 

The equilibrium equations that normally have to be considered in the EKR modeling of a soil contaminated by heavy metals can be classified into one of the following categories complex formation reactions, precipitation of the metal hydroxides or of other species, ion exchange reactions, surface complexation reactions, etc. Anyway, the autoionization of water always has to be considered and the precipitation of carbonates, together with the carbonate-bicarbonate equilibrium, should normally also be considered. However, the above equations have only considered the species in aqueous phase, so if a species precipitates, a new master species has to be included in this equilibrium system, whose concentration would be the amount of the precipitated species per unit volume of water. This additional degree of freedom is constrained by the solubility product constant of the precipitate (KO, because the new solid phase is in equilibrium with the aqueous phase. If there exists Np precipitated species, the pure-phase equilibria can be represented with the following equation ... 

Give the solubility-product-constant expressions and values (from Appendix D) for (a) barium carbonate, (b) silver sulfate. 

The availability of carbonate ions plays an important role in shell formation for a number of marine organisms, including stony corals ( FIQURE 17.18). These organisms, which are referred to as marine calcifters and play an important role in the food chains of nearly all oceanic ecosystems, depend on dissolved Ca and C03 ions to form their shells and exoskeletons. The relatively low solubility-product constant of CaC03,... 

Seashells and limestone are primarily calcium carbonate. Calcium carbonate is fairly insoluble, as you would expect from its solubility product constant (3.8 X 10 ). But it dissolves readily in acidic solution. Water that has filtered through decomposing vegetation contains carbonic acid, as well as other acids. When such an acidic solution comes into contact with limestone, it carves out caverns. The water is now a solution of calcium hydrogen carbonate. 

Strontianite (strontium carbonate) is an important mineral of strontium. Calculate the solubility of strontium carbonate, SrC03, from the solubility product constant (see Table 18.1). 

Magnesite (magnesium carbonate, MgC03) is a common magnesium mineral. From the solubility product constant (Table 18.1), find the solubility of magnesium carbonate in grams per liter of water. 

Once known, the solubility product constant can be used to determine the solubility of a sUghdy soluble salt. Suppose you wish to know how many moles of barium carbonate, BaCOg, can be dissolved in 1L of water at 25°C. From Figure 4.1, for BaCOg has the numerical value... 

Solubility of Carbon Dioxide in Water at Various Temperatures and Pressures Aqueous Solubility and Henry s Law Constants of Organic Compounds Aqueous Solubility of Inorganic Compounds at Various Temperatures Solubility Product Constants... 

The equilibrium constant for the dissolving of a sparingly soluble electrolyte is called the solubility product constant. The solubility product constant of lithium carbonate is... 

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