Determining the Molarity of a Saturated Solution

Purpose: The purpose is to determine the molarity of a asaturated solution at room temperature.

Background: In this experiment you will be given a sample of a known solute. Design an experiment to determine the molarity of a saturated solution. Molarity (M) is a unit used to indicate the concentration of a solution.

Procedure NOTE: Consult safety information and obtain teacher approval before beginning the experiment. Design a procedure to prepare a saturated solution and calculate the molarity of the saturated solution. You will be limited to 75 grams of solute. You may use any materials at your lab station and you may request additional materials.

Safety Information After reviewing your procedure, the instructor will discuss any safety precautions that are specific to your experiment.

Questions for further thought 1. Calculate the molarity of a solution that contains 17.54 g of KCl in 2.00 L of solution. 2. What mass of glucose (C6H12O6) would be required to prepare 2.00 L of a 1.50 M solution? 3. What is the relationship between temperature and the molarity of a saturated NaCl solution? 4. Phosphoric acid is usually obtained as an 87.0% (by mass) phosphoric acid solution. If it is 13.0 M, what is the density of this solution? What is its molality? 5. An aqueous solution of hydrofluoric acid is 30.0% HF, by mass, and has a density of 1.101 g cm-3. What are the molality and molarity of HF in this solution?

Prelab questions 1. What is the equation for molarity? 2. If you prepared a saturated potassium nitrate solution at room temperature and then raised the temperature 20 degrees Celsius, would you expect the solution to remain saturated? Explain your answer. 3. If a saturated glucose (C6H12O6) solution had a molarity of 3.28 M, calculate the grams of glucose that would be present in 100 mL of the saturated solution. Determining the Molality of a Saturated Solution

Purpose: The purpose is to determine the molality of a saturated solution at room temperature.

Background: In this experiment, you will be given a sample of a known solute. Design an experiment to determine the molality of a saturated solution. Molality is a unit used to indicate the concentration of a solution.

Procedure: NOTE: Consuslt safety information and obtain teacher approval before beginning the experiment. Design an experiment to prepare a saturated solution of a given solute and calculate the molality of the saturated solution. You will be limited to 75 g of solute. You may use any materials at your lab station and you may request additional materials.

Safety Information: After reviewing your procedure, the instructor will discuss any safety rpecautions that are specific to your experiment.

Questions for Further Thought 1. Calculate the molality of a solution that contains 20.00 g of KCl dissolved in 300 g of water. 2. What mass of glucose (C6H12O6) would be required to prepare a 3.00 m solution in 2.50 kg of water? 3. What is the relationship between temperature and the molality of a saturated NaCl solution? 4. Phosphoric acid is usually obtained as an 87.0% (by mass) phosphoric acid solution. If it is 13.0 M, what is the density of this solution? What is its molality? 5. An aqueous solution of hydrofluoric acid is 30.0% HF, by mass, and has a density of 1.101 g cm-3. What are the molality and molarity of HF in this solution?

Prelab questions 1. What is the equation for molality? 2. If you prepared a saturated potassium nitrate solution at room temperature and then raised the temperature 20 degrees Celsius, would you expect the solution to remain saturated? Explain your answer. 3. If a saturated glucose (C6H12O6) solution had a molality of 3.28 m, calculate the grams of glucose that would have to be added to 100 mL of water.