The document provides instructions for an experiment to determine the solubility of calcium hydroxide. The experiment involves preparing a saturated calcium hydroxide solution, standardizing hydrochloric acid, and then titrating the calcium hydroxide solution with the standardized acid. Students are advised to review solubility and the solubility product constant (Ksp) in their textbook before setting up calculations involving Ksp. The titration will have two equivalence points but sometimes only one will be visible, and students are told to continue titrating until their data plateaus.

1. Solubility of Calcium Hydroxide

2. Preparation Write the procedure for the experiment Procedure should contain enough detail so someone else could replicate it without additional information Determine the approximate mass of Ca(OH)2 to use for your saturated solution Both must be done before you come to class

3. Experiment Three parts Preparing saturated solution Standardization of HCl Determine [OH¯]

4. Saturated Solution Prepare saturated solution on Day 1 Save for Day 2 to complete titrations

5. Standardization of HCl Record exact mass of Na2CO3 used for each trial Do not refill HCl bottle during experiment Save HCl solution for next week’s lab

6. Titration: HCl and Ca(OH)2 Filter Ca(OH)2 before using Titration will have two equivalence points; sometimes only one will show

7. Ksp Review solubility and Kspin your textbook Setting up a Ksp expression Calculations involving Ksp

8. Experiment Tips Need three good titrations for each part Titration curves may only show one equivalence point even though there are two First one is sometimes hard to see Continue until data plateaus

9. Experiment Tips Record exact volumes used for all masses and volumes When using buret, estimate the second decimal place Mix after every addition to get accurate pH values