CHEM 214 General Chemistry II Lab - Experiment 009: Solubility Product Constant (Ksp) and Common-Ion Effect.

Document Content and Description Below

CHEM 214 General Chemistry II Lab - Experiment 009: Solubility Product Constant (Ksp) and Common-Ion Effect. Experiment 009: Solubility Product Constant (Ksp) and Common-Ion Effect References: Suz... anne Slayden, 2018, Chemistry 213, 214, 272 Laboratory Experiments, 7th Edition, pages 222-230. George Mason University, Department of Chemistry and Biochemistry. Solubility Product; 2020. Solubility Product, Distance Learning Summer 2020, accessed via Blackboard. CRC Handbook of Chemistry and Physics, 87th Edition. Journal of the American Chemical Society 2007, 129 (3), 118–120. https://doi.org/10.1021/ja069813z. Purpose The purpose of this experiment is to determine the solubility product constant (Ksp) of calcium iodate (Ca(IO3)2) and to analyze its common-ion effect. This will be done in two parts: Part A and Part B. Part A will titrate calcium iodate with sodium thiosulfate (Na2S2O3) and Part B will add more calcium iodate into the titration. The anticipated outcome is that the experimental Ksp would match the theoretical Ksp and the molar solubility of Part A would be less than the molar solubility of Part B. The balanced equations for this experiment are: Ca(IO3)2 (s) → Ca2+ (aq) + 2IO3- (aq) IO3- (aq) + 6S2O32- (aq) + 6H3O+ (aq) → I- (aq) + 3S4O62- (aq) + 9H2O (l)Materials • 0.1003-M Sodium Thiosulfate • Calcium Iodate • Calcium Iodate + Added Calcium Ions • 2-M HCl • Potassium Iodide (KI) • 0.2% Starch Solution • Distilled Water • Buret • 125-ml Erlenmeyer Flask • 50-mL Graduated Cylinder Procedure 1. Rinse a buret with pre-standardized sodium thiosulfate solution. Record its concentration. Measure 50 mL of sodium thiosulfate solution and then transfer to buret. 2. Add 5 mL of calcium iodate saturated solution to the 125-mL Erlenmeyer flask and then add 20 mL of distilled water. Add about 1 gram of the KI into the calcium iodate/water solution, and then add 20 drops of the 2-M HCl. Swirl to mix. Add about 30-40 10 drops of the 0.2% starch solution to complete sample preparation. Make 3 samples for the Scout Titration, Trial One, and Trial Two. Begin titrating each sample with the sodium thiosulfate solution until the equivalence point is reached. 3. Repeat Step 2 using the calcium iodate solution with the added calcium ions, making a total of 6 samples. [Show More]

Last updated: 1 year ago

Preview 1 out of 18 pages