Read the material at the link below and do the problems at the end. For example , if we wanted to find the K sp The solubility product constant, \(K_{sp}\) , is the equilibrium constant for a solid substance dissolving in an aqueous solution. The solubility product constant is the equilibrium constant for the dissolution of a solid substance into an aqueous solution. This is referred to as a formula of the type , where  is the cation and  is the anion. Use the molar mass to convert from molar solubility to solubility. The first type of calculation we will look at is how to calculate the solubility of a substance in moles per litre (M), given the value of Ksp . In this case, each formula unit of CaCO 3 yields one Ca 2+ ion and one CO 3 2− ion. An unsaturated solution is a solution in which all solute has dissolved. In other words, there is a relationship between the solute's molarity and the solubility of the ions because K sp is literally the product of the solubility of each ion in moles per liter. This is referred to as a formula of the type , where is the cation and is the anion. Ksp is used to determine whether a precipitate should form from a solution of known ionic concentration. Pressure can also affect solubility, but only for gases that are in liquids. The diverse-ion effect (if the ions of the solutes are uncommon, the value of Ksp will be high). Solubility is defined as the maximum amount of solute that can be dissolved in a solvent at equilibrium. In case of pure solid substances the concentration remains constant, and so we can say: \(K_{sp}\) = \(K[BaSO_4]\) = \([Ba^{2+}][SO^{4-}]\). The concentration of each of the ions at equilibrium is 6.7 × 10 -5  M. We can use the molar mass to convert from molar solubility to solubility. Solubility depends on a number of parameters amongst which lattice enthalpy of salt and solvation enthalpy of ions in the solution are of most importance. The molar solubility of a substance is the number of moles that dissolve per liter of solution. For very soluble substances (like sodium nitrate, NaNO 3), this value can be quite high, exceeding 10.0 moles per liter of solution in some cases.. For insoluble substances like silver bromide (AgBr), the molar solubility can be quite small. Ksp = [Ag⁺] [Cl⁻] Solubility Product Formula. The variable  will be used to represent the molar solubility of CaCO 3 . The solubility of ionic compounds (which disassociate to form cations and anions) in water varies to a great deal. The relation between solubility and the solubility product constants is that one can be used to find the other. The process of determining solubilities using. The known Ksp values from the Table above can be used to calculate the solubility of a given compound by following the steps listed below. Solubility product constant is simplified equilibrium constant (Ksp) defined for equilibrium between a solids and its respective ions in a solution. In this case the setup of the ICE table would look like the following: When the K sp expression is written in terms of , we get the following result for the molar solubility. This is the solubility product principle. The solubility of a substance in a solvent is the total amount of the solute that can be dissolved in the solvent at equilibrium. Ksp - Solubility product constant definition. http://www.tonywhiddon.org/lhs/apchemistry/studyguides/solubility/ksp.htm, http://commons.wikimedia.org/wiki/File:Luke_AFB_waste_water_treatment_plant_1982.JPEG, http://www.ck12.org/book/CK-12-Chemistry-Concepts-Intermediate/, Set up an ICE problem (Initial, Change, Equilibrium) in order to use the. Therefore, the solubility product constant can be expressed as: The chemical formula of common salt is NaCl. A saturated solution is said to be in a state of dynamic equilibrium between the ionic compound and the undissolved solid. Solubility depends on temperature and it is different for every salt. The simple concept of solubility of a substance is the molarity of the material under excessive undissolved material in a solution at chemical equilibrium. The nature of the solvent determines the amount of energy released during solvation that is solvation enthalpy. The Table below shows the relationship between Ksp and molar solubility based on the formula. The Ksp of calcium carbonate is 4.5 × 10 -9 . It is denoted by the symbol Ksp. For example , if we wanted to find the K sp The solubility product constant is used to describe the saturated solutions of ionic compounds having relatively low solubility. 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