Unit 10 Solutions Homework Packet

Name: ______Period: ______

Part A: Solubility Curves- Answer the following questions using the solubility curve below. Include units!

1)What mass of each solute will dissolve in 100mL of water at the following temperatures?

KNO3 at 70°C = ______
NaCl at 100°C= ______
NH4Cl at 90°C= ______
KClO3 at 10°C= ______
Which of the above three substances is most soluble in water at 15°C? ______

2)Which of the substances (if any) on the solubility curve gases? How do you know?

3)Which compound is most soluble at 20 ºC? ______

4)Which is the least soluble at 40 ºC? ______

5)Which substance is least soluble at 10C? ______

6)How much NH4Cl can be dissolved in 200 g of H2O at 50C? ______

7)How much NaCl can be dissolved in 500 g of H2O at 100C? ______

8)How much NH3 can be dissolved in 300 g of H2O at 20C? ______

9)A mass of 15 g of KClO3 is dissolved in 100 g of water at 40 ºC. The solution is heated to 80ºC. How many more grams of potassium chlorate must be added to make the solution saturated? ______

10)A mass of 80 g of KNO3 is dissolved in 100 g of water at 50 ºC. The solution is heated to 70ºC. How many more grams of potassium nitrate must be added to make the solution saturated? ______

11)A mass of 70 g of NaNO3 is dissolved in 100 g of water at 10 ºC. The solution is heated to 35ºC. How many more grams of sodium nitrate must be added to make the solution saturated? ______

12)A solution of KClis saturated in 100 g of water at 80 ºC. The solution is cooled to 60ºC to become supersaturated. How much excess KCl is dissolved in solution?______

13)A solution of NaNO3 is saturated in 100 g of water at 40 ºC. The solution is cooled to 20ºC to become supersaturated. How much excess NaNO3 is dissolved in solution?______

14)On a solubility curve, the points on the curve indicate a ______solution.

15)Values on the graph ______a curve represent unsaturated solutions.

Label the following solutions as saturated, unsaturated, or super saturated. If unsaturated, write how much more solute can be dissolved in the solution.

16)A solution that contains 70g of NaNO3 at 30°C (in 100 mL H2O): ______

17)A solution that contains 50g of NH4Cl at 50°C (in 100 mL H2O): ______

18)A solution that contains 70g of KI at 0°C (in 100 mL H2O): ______

19)A solution that contains 20g of KClO3 at 50°C (in 100 mL H2O): ______

20)A solution that contains 20g of NH3 at 80°C (in 100 mL H2O): ______

Part B: Concentration- Answer the following questions. Show ALL WORK and include units!

1)Calculate the molarity of 0.060 moles NaHCO3 in 1500. mL of solution.

2)What is the molality of a solution made by dissolving 23.2 g of sodium nitrate in 250.0 g of water?

3)What is the molar concentration of 1.0 mol of KCl dissolved in 750. mL of solution?

4)How many grams of silver bromide must be dissolved in 725 grams of water to make a 0.220 m (molal) solution?

5)Calculate the molarity of 34.2 grams of sugar, C12H22O11 in 500. mL of solution.

6)What mass of solvent must be added to 17.3 g of bromine to make a 0.115 m (molal) solution?

7)Calculate the number of moles of NaCl contained in 0.500L of a 1.5M solution.

8)What is the mole fraction of ethanol when 23.2 g of ethanol are mixed with 73.1 g of water?

9)Calculate the number of moles of NaOH contained in 250. mL of a 0.05M solution.

10)How many grams of water must be added to 72.8 grams of sodium chloride to make the mole fraction of sodium chloride 0.200?

11)If 10.7 g of NH4Cl is dissolved in water to make 800 mL of solution, what will be its molarity?

12)285 g of sucrose (C12H22O11) are added to 1250g of water. Find both the molality and the mole fraction of sucrose.

13)Calculate the molarity of a solution prepared by dissolving 6.80 grams of AgNO3 in enough water to make 2.50 liters of solution.

14)Calculate the mole fraction of NaOH in a 10.0 m aqueous solution.

15)Whatvolume of solvent is required to prepare of 0.700 M CaCl2 using 0.85g of CaCl2?

16)How many moles, of CaCl2 will be required to prepare the above solution?

17)How many grams of KNO3 will be required to prepare 800 mL of 1.40 M KNO3?

18)Calculate the volume of a 1.25 M solution of HCN made from 31.0 grams of HCN.

19)Calculate the volume of a 3.50 molar solution of H2SO4 made from 49.0 grams of H2SO4?

mass of empty volumetric flask: / 146.89 g
mass of weighing dish + sucrose: / 29.1439 g
mass of weighing dish after adding sucrose to volumetric flask: / 23.5739 g
mass of filled volumetric flask: / 199.34

20)A solution is prepared by taking a clean and dry 50.00 mL volumetric flask. Some sucrose (table sugar; 342.2 g/mol) is added to the flask, with the following mass measurements recorded. Some water is added to the flask, the solution stirred until all the sucrose is dissolved. Then water is added carefully to the mark on the flask. The filled flask is then weighed again:

Determine the following concentrations, all with reference to the sucrose as the solute:

Molarity of solution:

Molality of sucrose:

mole fraction of sucrose:

percent by mass sucrose

Part C: Solution Stoichiometry- Answer the following questions. Show ALL WORK and include a balanced equation and units!

1)Your teacher asks you to prepare 500 mL of a 2.75 molar solution of NaCl for a lab. Write a step-by-step procedure describing how you would carry outthis task.

2)Your teacher asks you to prepare 250 mL of a 0.35M solution of HC2H3O2 for an upcoming lab. Write a step-by-step procedure describing how you would carry outthis task.

3)If 10.0 mL of a 2.25 M sodium carbonate solution reacts with excess iron (III) chloride solution, what mass of iron (III) carbonate precipitates out of solution? ___FeCl3(aq) + ___Na2CO3(aq) ___Fe2(CO3)3(s) + ___NaCl(aq)

4)A chemist reacts 75.0 mL of 0.200 molar iron (Ill) chloride solution completely with an excess of 0.250 M sodium carbonate solution. What volume of sodium carbonate solution is needed?

5)What volume of 0.20 M AgNO3 will be needed to react completely with 25.0 mL of 0.50 M potassium phosphate?

6)What mass of precipitate is produced from the above reaction?

7)What mass of precipitate should result when 0.550 L of 0.500 mol/L aluminum nitrate solution is mixed with 0.240 L of 1.50 mol/L sodium hydroxide solution?

8)If 25.0 mL of 0.750 MCopper (II) sulfate solution is mixed with excess sodium chloride solution, what is the theoretical yield of copper (II) chloride (sodium sulfate is the other product)?

9)What is the limiting reactant if 0.50 L of 0.50 MCopper (II) sulfate solution is mixed with 0.50L of 0.50 mol/L sodium chloride solution?

Part D: Colligative Properties- Answer the following questions.

1)What is a colligative property?

2)What property are colligative properties dependent on?

3)What is a van’t Hoff factor?

4)List 2 examples of colligative properties.

5)Which would freeze faster a 0.50M solution of sugar water or a 1.0M solution of sugar water? ______Which would boil faster? ______

6)Which would freeze faster a 0.50M solution of sugar water or a 0.50M solution of calcium chloride water? ______Which would boil faster? ______

7)Which would freeze faster a 3.0M solution of acetic acid or a 1.0M solution of acetic acid water? ______Which would boil faster? ______

8)Which would freeze faster a 0.20 M solution of aluminum sulfide or a 0.20M solution of phosphoric acid? ______Which would boil faster? ______

9)How will adding 10.0g of sodium chloride to a 0.10M solution of salt water affect…?

Concentration?Increase or Decrease
Boiling Point?Increase or Decrease
Freezing Point?Increase or Decrease

10)How will adding 100mL of solvent to a 0.10M solution of salt water affect…?

Concentration?Increase or Decrease
Boiling Point?Increase or Decrease
Freezing Point?Increase or Decrease

11)For a 0.450m solution of calcium chloride in water, calculate the freezing point and the boiling point of the solution. The Kf = 1.855 and the Kb = 0.512.

12)Calculate the freezing point and boiling point for a 4.90m aqueous solution of sodium acetate. Kf = 1.855 and Kb = 0.512

13)For a 0.780m solution of sulfuric acid in water, calculate the freezing point and the boiling point of the solution. The Kf = 1.855 and the Kb = 0.512.

14)Using colligative properties, in complete sentences explain why we add antifreeze to the solution in our engines in the winter time. Discuss concentration, freezing point, and importance of antifreeze.

15)Create a model of the molecular level of the solution before and after antifreeze was added. Include a key.

Part E: Dilutions- Answer the following questions. Show ALL WORK and include units.

1)What is a dilution?

2)Describe the step-by-step process of diluting 0.50L of a 1.0M solution of NaCl to a 0.50M solution of NaCl.

3)In question number 2, during the dilution, what happened to…

The concentration? Increase – Decrease – Remain the same
The volume of the solution?Increase – Decrease – Remain the same
The amount of solvent?Increase – Decrease – Remain the same
The amount of solute? Increase – Decrease – Remain the same

4)Model the solution on the molecular level from number 2 before and after the dilution. Include a key if necessary.

BEFORE / AFTER
KEY

Answer the following questions. Show ALL WORK and include units.

5)If 45 mL of water is added to 250mL of a 0.75 M K2SO4 solution, what will the molarity of the diluted solution be?

6)If water is added to 175mL of a 0.45 M KOH solution until the volume is 250 mL, what will the molarity of the diluted solution be?

7)How much 0.075 M NaCl solution can be made by diluting 450 mL of 9.0 M NaCl?

8)If 550mL of a 3.50 M KCl solution are set aside an allowed to evaporate until the volume of the solution is 275 mL, what will the molarity of the solution be?

9)How much water would need to be added to 750 mL of a 2.8 M HCl solution to make a 1.0M solution?

10)If I add water to 100 mL of a 0.15 M NaOH solution until the final volume is 150 ML, what will the molarity of the diluted solution be?

11)How much 0.05 M HCl solution can be made by diluting 250 mL of a 10 M HCl solution?

12)I have 345 mL of a 1.5 M NaCl solution. If I boil the water until the volume of the solution is 250 mL, what will the molarity of the solution be?

13)How much water would I need to add to 500 mL of a 1.0 M KCl solution to make a 2.4 M solution?

14)How much of a 5.00 M stock solution of copper (II) sulfate is needed to make 500.0 mL of a 0.35M solution?

15)If 6.0L of a 1.50 M AgNO3 solution is set aside an allowed to evaporate until the volume of the solution is 4.2L, what will the molarity of the solution be?

16-20)Which of the following has a higher concentration? Circle the correct answer: Solution A, Solution B, or They have an equal concentration

Part F: Solutions Vocabulary

Fill in the blank using the most appropriate vocabulary word or phrase.

1)A solution is a ______mixture.

2)In a carbonated drink like Dr. Pepper, the solute is in the ______state of matter, the solvent is in the ______state of matter, and together they make a solution that is in the ______state of matter.

3)Liquids, such as antifreeze and water, which dissolve in one another are said to be ______, while liquids that do not dissolve in one another, such as salad oil and vinegar are said to be ______.

4)Brass, a mixture of copper and zinc, is an example of a solid solution known as a(n) ______.

5)Because the particles in a solution are so small, ______cannot be used to separate the components no do the components settle upon standing.

6)The rate of dissolution expresses how ______a solute dissolves in a solvent.

7)A solution is ______if it contains a relatively large amount of solute. A solution is ______if it contains a relative small amount of solute.

8)List at least 3 ways concentration is measured in. ______

9)What is the most common way to express concentration in chemistry? ______

10)List an example of each of the following types of solutions:

Solid solute in liquid solvent: ______
Gas solute in liquid solvent: ______
Solid solute in solid solvent: ______
Liquid solute in liquid solvent: ______

11)A ______is a graphical representation of solubility of substances.

12)A ______solution is a solution at its maximum concentration for a given temperature and pressure.

13)A ______solution is a solution that has not reached its maximum concentration.

14)A ______solution is a solution that contains more solute than it saturation limit.

Answer the following questions in complete sentences.

15)Explain the phrase “like dissolves like”. Give an example and a non-example.

16)What are 3 ways solutions can be separated? What type of solution is best for each separation technique?

17)What is the proper technique for measuring volume?

18)What piece of glassware is used for making solutions? ______

19)What piece of glassware is used to measure an amount of volume? ______

20)What two pieces of glassware is used to hold or mix chemicals? ______and ______

21)What substance is the universal solvent and how did it get this nickname?

22)Give an example of a solution and describe the solute and solvent.

23)Explain the terms solubility, soluble, and insoluble.

24)Is it possible to dissolve a 5 pound back of flour in a cup of milk? Explain why or why not.

25)What is equilibrium solubility?

26)How are supersaturated solutions made?

27)What is concentration and why is it important?

28)How do you test for saturation? Explain the potential results.

29)Explain how a solution can be both dilute and saturated at the same time.

30)Correct the following procedure for creating 1.00 L of a1.00 M sodium chloride solution.

Use a scale to measure 1 mole of sodium chloride and place in graduated cylinder.
Use an Erlenmeyer flask to measure 1 L of water and place in same graduated cylinder and mix.

31)What are two ways to measure concentration experimentally?

32)What is the most important solution in your life and why?

33)Describe the process of NaCl dissolving in water. Be detailed and specific.

34)If you were making a solution of lemonade and you wanted the solute to dissolve faster, list at least 3 different things you could increase the rate of dissolution.

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