11th grade chemistry worksheets

Solubility How is the quantity of solute in a saturated solution determined? Why? When we add salt to a pot of boiling water or sugar to a pitcher of iced tea, we expect that the added solute will completely dissolve. It requires a large quantity of these solutes to saturate a solution. On the other hand, water has flowed over rock riverbeds for centuries and only dissolved enough material in some cases to provide a trace of certain minerals in the water. Different solutes, such as salt, sugar, or minerals, dissolve to very different extents in water (and other solvents). In this activity you will learn how to quantify the amount of solute that is dissolved in a saturated solution. Model 1 – Three Solutions The following data refer to three experiments in which solute is added to water in a beaker at 20 ºC. The mixtures are stirred and then allowed to sit for three hours before measuring the amount of solid that dissolves. Ten separate trials are conducted for each experiment. The same solute is used in all three experiments. Experiment 1 In 10.0 g water Experiment 2 In 20.0 g water Experiment 3 In 50.0 g water Trial Mass of solute added (grams) Mass of solute dissolved (grams) Mass of solute added (grams) Mass of solute dissolved (grams) Mass of solute added (grams) Mass of solute dissolved (grams) 1 1.0 1.0 1.0 1.0 3.0 3.0 2 2.0 2.0 2.0 2.0 6.0 6.0 3 3.0 3.0 3.0 3.0 9.0 9.0 4 4.0 3.6 4.0 4.0 12.0 12.0 5 5.0 3.6 5.0 5.0 15.0 15.0 6 6.0 3.6 6.0 6.0 18.0 18.0 7 7.0 3.6 7.0 7.0 21.0 18.0 8 8.0 3.6 8.0 7.2 24.0 18.0 9 9.0 3.6 9.0 7.2 27.0 18.0 10 10.0 3.6 10.0 7.2 30.0 18.0 1. Identify the variable(s) that were controlled among all three experiments in Model 1. 2. What variable(s) were changed purposefully among the three experiments in Model 1? Solubility 1 3. What experimental question can be answered by analyzing the data in the three experiments in Model 1? Use the words “solvent” and “solute” in your question.