Calculating Solubility Unit III: Solubility Equilibrium

Calculating Solubility Example 1 It is experimentally found that 1L of saturated AgBrO 3 (aq) contains 1.96 g of AgBrO 3. What is the molar solubility of AgBrO 3 ?

Calculating Solubility Example 2 The molar solubility of PbI 2 is 1.37 x M. Express this value in grams per litre.

Calculating Solubility Example 3 It is experimentally found that 250 mL of saturated CaCl 2 contain 18.6 g of CaCl 2. What is the solubility of CaCl 2 ?

Calculating Solubility Example 4 (Hebden p. 78 #15) A chemistry student was assigned the task of determining the solubility of potassium chloride, KCl. She added an excess of solid KCl to water, stirred, and let the solution sit overnight. The next day, she pipetted a mL portion of the saturated solution into a pre-weighed evaporating dish, determined the combined mass, carefully boiled off the water present, allowed the residue to cool and re-determined the mass of the evaporating dish and residue. The data obtained is given below.

Calculating Solubility Temperature of solution= 22.5ºC Mass of evaporating dish= g Mass of solution and evaporating dish= g Mass of residue and evaporating dish= g Calculate: a) The mass of mL of the solution. b) The mass of KCl in mL of solution. c) The mass of water in mL of solution. d) The mass of KCl which can dissolve in g of water at 22.5ºC. e) The molar solubility of KCl, expressed in moles of KCl per litre of solution.

Calculating Ion Concentrations Example 5 Calculate the concentration of all ions in each of the following solutions. a) 2.5 M CaCl 2

Calculating Ion Concentrations Example 5 (continued) Calculate the concentration of all ions in each of the following solutions. b) 0.68 M Al 2 (SO 4 ) 3

Calculating Ion Concentrations Example 5 (continued) Calculate the concentration of all ions in each of the following solutions. c) 8.0 g of KBr in 500 mL

Calculating Ion Concentrations It will also be necessary to take into account the dilution that occurs when solutions of ions are mixed with water or each other. C 1 V 1 = C 2 V 2

Calculating Ion Concentrations Example 6 Calculate the concentration of all the ions present when: a) 150 mL of water is added to 125 ml of 0.25 M Cl -

Calculating Ion Concentrations Example 6 (continued) Calculate the concentration of all the ions present when: b) 25.0 mL of M Ag + is added to 55.0 mL of M NO 3 -

Calculating Ion Concentrations Example 6 (continued) Calculate the concentration of all the ions present when: c) 15.0 mL of 0.75 M MgCl 2 is mixed with 30.0 mL of 0.60 M CaBr 2

Calculating Ion Concentrations Example 6 (continued) Calculate the concentration of all the ions present when: d) 65.0 mL of M AgNO 3 is mixed with 80.0 mL of M Ba(NO 3 ) 2

Solubility Graph

Assignment