Water solubility product constant

Isotope ratio mass spectrometry International Standards Organization Known or known sample Acid dissociation constant Base disscxdation constant Distribution coefficient Henry s Law constant Solubility product constant Water dissociation constant,... 

Solubility Product — The solubility product constant commonly referred to as the solubility product provides a convenient method of predicting the solubility of a material in water at equilibrium. Copper hydroxide, for example, dissolves according to the following equilibrium ... 

One way to establish equilibrium between a slightly soluble solid and its ions in solution is to stir the solid with water to form a saturated solution. As you might expect, the solubility of the solid, s, in moles per liter, is related to the solubility product constant, Ksp. In the case of barium sulfate dissolving in water we have... 

K. See Equilibrium constant Ka. See Acid equilibrium constant See Base equilibrium constant Kc. See Equilibrium constant Kf. See Formation equilibrium constant Kr See Equilibrium constant K,p. See Solubility product constant K . See Water ion product constant K-electron capture The natural radioactive process in which an inner electron (n = 1) enters the nucleus, converting a proton to a neutron, 514 Kelvin, Lord, 8... 

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. 

In this section, you determined the solubility product constant, Kgp, based on solubility data. You obtained your own solubility data and used these data to calculate a value for Kgp. You determined the molar solubility of ionic solutions in pure water and in solutions of common ions, based on their Ksp values. In section 9.3, you will further explore the implications of Le Chatelier s principle. You will use a reaction quotient, Qsp, to predict whether a precipitate forms. As well, you will learn how selective precipitation can be used to identify ions in solution. 

Since the dissolution of a slightly soluble salt in water is an equilibrium, an equilibrium expression can be written. This expression is known as the solubility product. The constant for the expression is named the solubility product constant and denoted by K p. For example, the solubility product for the reaction below ... 

A potentiometric method for determination of ionization constants for weak acids and bases in mixed solvents and for determination of solubility product constants in mixed solvents is described. The method utilizes glass electrodes, is rapid and convenient, and gives results in agreement with corresponding values from the literature. After describing the experimental details of the method, we present results of its application to three types of ionization equilibria. These results include a study of the thermodynamics of ionization of acetic acid, benzoic acid, phenol, water, and silver chloride in aqueous mixtures of acetone, tetrahydrofuran, and ethanol. The solvent compositions in these studies were varied from 0 to ca. 70 mass % nonaqueous component, and measurements were made at several temperatures between 10° and 40°C. 

As an alternative to laboratory solubility measurements, solubility product constants (KSp), which are derived from thermodynamic data, can be used to calculate the solubility of solids in water (Table 2.9). Each solubility product constant describes a disassociation of a solid in water and calculates the activities or concentrations of the dissolution products in the saturated solution. The solubility product constant or another equilibrium constant of a reaction may be derived from the Gibbs free energy of the reaction (AG"K) as shown in the following equation ... 

Table 2.9 Equilibrium constants (including some solubility product constants, Ksp values, from Lide (2007), Krause and Ettel (1988), Bothe and Brown (1999), Davis (2000), Nordstrom and Archer (2003), Langmuir, Mahoney and Rowson (2006), Lee and Nriagu (2007), Zhu et al. (2005), and Zhu et al. (2006)) for reactions with various arsenic compounds in water at 1 bar pressure. pK = -logw K. ... 

By definition the reactant for any solubility product constant reaction must be a solid and the solvent must be water, so this is the general form of any Ksp and the equation always simplifies down to a nonfraction. From this expression the solubility of Ca3(As04)2-4.25H20 is easily calculated. Based on Equation 2.31, the dissolution of 1 mole of the solid will generate three moles of Ca2+ and two moles of AsCL3-. Therefore ... 

Solubility product constant An equilibrium constant that describes the dissolution of a solid in water. Solute A substance that will dissolve into a solvent or that has dissolved into a solvent. 

In complex solutions such as estuarine waters, where the proportion of ions in solution is commonly not the same as that in the solids from which they are derived, it is necessary to use the solubility product constant defined as KSp = [A ] [B-]. To determine the degree to which a solution is supersaturated or undersaturated, the ion activity product (IAP) can be compared to the Ksp. 

Solubility product constant constant Ksp that indicates the degree to which a compound dissociates in water. 

The logarithm of the quotient of the ion activity product (IAP) and solubility product constant (KSP) is called the saturation index (SI). The IAP is calculated from activities that are calculated from analytically determined concentrations by considering the ionic strength, the temperature, and complex formation. The solubility product is derived in a similar manner as the IAP but using equilibrium solubility data corrected to the appropriate water temperature. 

Recall from previous chapters that solubility is the amount of a solid that it takes to saturate the solution that it is in. Also remember that not every salt is completely soluble in water. The solubility product constant helps determine how soluble a salt is in solution at a particular temperature. The values for these constants can be found in Appendix 4, Reference Tables, in the back of this book. 

Consider the chemical equation for AgCl dissolved in water to make a saturated solution AgCl(s) <—> Ag1+(aq) + Cl1 (aq). At 298 K the solubility product constant is 1.8 x 10-10, which indicates that is a slightly soluble salt. There is a way of making AgCl even less soluble, via the common ion effect. Consider the following, when an ion that is already present is added to the solution, the equilibrium will shift to consume the increase in concentration of the ion. 

The solubility of Pbl2 in water at 20°C is 1.37 x 10 3 molal for this temperature the numerical value of 0.5092 must be replaced with 0.5071. (a) Determine the solubility product constant at 20°C. Determine the solubility of Pbl2 in a 0.30 molal solution of KI in water. 

Determine the solubility product constant of PbS04 in water. 

To gain an insight into the sulfide stabilization, examine the solubility product constants for the sulfides and phosphates of hazardous metals listed in Table 16.4. In this table, except for barium sulfide, other sulfides as well as phosphates have very high pK p, indicating that their aqueous solubility is almost negligible. In particular, the pA sp of HgS and Ag2S is very high, and these two sulfides are insoluble in water. Therefore, when a waste stream contains one of these two, sulfide pretreatment followed by phosphate ceramic formation is an ideal way to treat the waste stream. 

A suite of both oxidized and reduced iron minerals has been found as efflorescences and precipitates in or near the acid mine water of Iron Mountain. The dominant minerals tend to be melan-terite (or one of its dehydration products), copiapite, jarosite and iron hydroxide. These minerals and their chemical formulae are listed in Table III from the most ferrous-rich at the top to the most ferric-rich at the bottom. These minerals were collected in air-tight containers and identified by X-ray diffractometry. It was also possible to check the mineral saturation indices (log Q(AP/K), where AP = activity product and K = solubility product constant)of the mine waters with the field occurrences of the same minerals. By continual checking of the saturation index (S.I.) with actual mineralogic occurrences, inaccuracies in chemical models such as WATEQ2 can be discovered, evaluated and corrected (19), provided that these occurrences can be assumed to be an approach towards equilibrium. 

Solubility product constant the constant for the equilibrium expression representing the dissolving of an ionic solid in water. (8.8)... 

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 ... 

Most parts of the oceans are nearly saturated with CaF2. The mineral fluorite, CaF2, may precipitate when ocean water evaporates. A saturated solution of CaF2 at 25°C has a solubility of 3.4 x 10 " M. Calculate the solubility product constant for CaF2. 

Copper(I) chloride has a solubility product constant of 1.2 x 10 " and dissolves according to the equation below. Calculate the solubility of this salt in ocean water in which the [CF] = 0.55. 

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

The product of and the concentration of the undissolved solid creates a new constant called the solubility product constant, The solubility product constant is an equilihrium constant for the dissolving of a sparingly soluble ionic compound in water. The solubility product constant expression is... 

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