**Procedure:**

1. Open the simulation. Select "File" in the upper left corner to open the assignment. Choose "Load an Assignment" from the dropdown list.
2. In the assignment list, select "Solubility and Solids." Choose "Temperature and the Solubility of Salts" lab by selecting the arrow to the right of the title. This will take you to the lab.
3. In the Stockroom, there are three tabs: Solutions, Glassware, and Tools. Select the Solutions tab. In the list of solutions, select "Distilled Water." This will place a carboy of distilled water on the lab bench. Return to the Stockroom.
4. In the Glassware list, select "Beakers" and choose a 600 mL beaker. This will place the beaker on the lab bench.
5. Select and hold the carboy of distilled water, and move it over on top of the beaker. A measurement box will appear. Add 100 mL of water to the beaker. Return to the Stockroom.
6. In the Tools list, select the Bunsen burner. Place the Bunsen burner under the beaker of water, and heat it to 100 °C. Keep the Bunsen burner under the beaker, and return to the Stockroom.
7. In the Solutions list, select copper sulfate (\(\text{CuSO}_4(s)\)). Select and hold the bottle of copper sulfate, and move it on top of the beaker. A measurement box will appear. Add 50.00 g of \(\text{CuSO}_4(s)\) to the water in the beaker. You will observe the water change color to blue. Record the amount of copper sulfate added to the beaker.
8. Select the beaker. The panel to the left will show data on the different components in the beaker. As you continue to add copper sulfate to the water, the solution will become saturated. When the solution is supersaturated, you will begin to see the weight of crystals that form (in grams) in this panel.
9. Add increments of 1.00 g of \(\text{CuSO}_4(s)\) to the beaker until evidence of crystal formation appears in the panel to the left. You will not be able to observe the crystals in the beaker. Record how much \(\text{CuSO}_4(s)\) you have added (however many grams you added one by one, plus the original 50).
10. Calculate the concentration of aqueous \(\text{CuSO}_4(aq)\) in g/L at the point of saturation at 100 °C.
11. Add 5.00 mL of water to the beaker. You should notice that the solid \(\text{CuSO}_4(s)\) in the beaker drops to zero. Calculate the concentration of the aqueous system now.
12. Take the beaker off the heat. As the temperature drops, solid \(\text{CuSO}_4(s)\) will reappear. Record the temperature at which this happens. The temperature will drop quickly. You may need to put the beaker back on the heat and watch the drop a few times to get an accurate reading.
13. Record the temperature at which the solid reappears.
14. Place the beaker back on the burner.
15. Repeat steps 10–12 eight more times.
16. Plot a graph showing the relationship between temperature on the independent axis and concentration of \(\text{CuSO}_4(aq)\) on the dependent axis.
17. Repeat the entire procedure for either potassium chloride (\(\text{KCl(s)}\)) or cesium sulfate (\(\text{Ce}_2(\text{SO}_4)_3(s)\)). Note that if a solid appears immediately upon adding 50 g, you will need to put that beaker away, start over again, and simply add less. You need to add solid reagent bit by bit until saturation. You don’t want to start with too much.

**Communicating Your Results:**

Communicate your results in a lab report. Your lab report should include the following sections: testable question, hypothesis, materials, procedure (including your identified variables), observations, results, discussion, and conclusion.

Your results and discussion section of your report should include the following:

- Your results section should include charts showing your raw data and graphs showing your solubility curves. You should also calculate the solubility constant (which is just the slope of the curve expressed as a decimal number with units; the units are the unit of the dependent axis/the unit of the independent axis) for each of the solutes that you tested. Show all of your calculations.
- Your discussion section should state your conclusions. Describe in sentences what you found and the significance of it. What limitations were there to this experiment? How might you modify the procedure in the future to be more accurate or precise? Why is knowing the solubility constant of different compounds important or useful? Answer these and any other questions that you had while you were conducting these trials. What other tests could be done in the future? How could the knowledge be used?