Milwaukie HS • Chemistry • Linman/Herrington Name ______Period ___ Date ___/___/___ W601 Webquest

Click on the following website to go to your first site http://www.solubilityofthings.com/basics/

1. What are the two parts of a ? ______2. Define a solute: 3. Define : 4. What does a solution measure? ______5. Concentrated have a ______amount of solute. 6. Diluted solutions have a ______amount of solute. 7. Describe an unsaturated solution:

8. Describe a saturated solution:

9. What happens when you add more solute to an unsaturated solution?

10. What happens when you add more solute to a saturated solution?

11. Why is water called a “universal solvent”? 12. What makes water so good at dissolving other things? 13. What two factors affect the most?

14. What is the difference between a and a ?

Click on the following website to go to your second site... http://www.chem.purdue.edu/gchelp/solutions/character.html 15. The concentration of a solution...... is a...... represents...... can be...

16. What is the difference between DILUTE and CONCENTRATED?

17. Define Unsaturated: 18. Define Saturated: 19. Define Solubility:

20. There are a ______of ways to express the relative amounts of solute and solvent in solution.

21. List four ways to express concentration: 1. 3. 2. 4.

22. What TWO things must you have to compute the following... Molarity ______Molality ______

23. Does temperature affect the following computations? Molarity ______Molality ______

24. What is the difference between MOLARITY and ?

Click on the following website to go to your third site... http://dl.clackamas.edu/ch105-04/molarity.htm

25. What is the most common way of expressing ?

26. What is the formula for MOLARITY? 27. What is the unit that is used to for MOLARITY? 28. What symbol represents MOLARITY? 29. What is the difference between MOLES and MOLARITY?

Click on “Calculations Using Molarity” on left side of screen 30. What are the 3 types of calculations you need to be able to do with Molarity? a. b. c. 31. Do the “Calculating Molarity from moles and volume” Ex 3b. Show Work!

32. Do the “Calculating Molarity from mass and volume” Ex 3c. Show Work!

33. Do the “Calculating mass of solute from Molarity” Ex 3d. Show Work!

Read the following article: http://chemistry.about.com/library/weekly/aa121602a.htm

How does this article relate to our class in your opinion (Please write in complete sentences)

Can you find another link to solution chemistry in the real world? List it here:

Milwaukie HS • Chemistry • Linman/ Herrington Name ______Period ___ Date ___/___/___ A601 Solutions

Classify the following as homogeneous or heterogeneous: A: Freshly squeezed orange juice B: Tap water C: Human Blood D: Sand

1. Does a solution have to be a liquid ? Explain why or why not.

2. Name the solute and the solvent in aqueous sodium chloride solution, NaCl(aq).

3. How is distillation used to prepare pure water from tap water

4. Why are gas bubbles not visible in an unopened bottle of soda?

5. Explain what happens to gases dissolved in the blood when a diver returns to the water’s surface very quickly

6. How does rising temperature affect the solubility of gases in water?

7. Why do bubbles escape from soda that has just been opened?

8. Name two factors that affect solubility.

Milwaukie HS • Chemistry • Linman/ Herrington Name ______Period ___ Date ___/___/___ A602 Solutions: Molarity and Solubility

1. What is the molarity of solution made from the equivalent of 125 g of sodium nitrate in 1.0 L of solution?

Answer:______2. What final volume in liters of a 2.5 M solution of sodium nitrate can be made using 25.0g of solute?

Answer:______3. What mass in grams of sodium nitrate , is needed to make 85.0 ml of a 0.2500 M solution?

Answer:______4. A saturated sodium nitrate solution at 10 oC will have how many grams of sodium nitrate dissolved in 100 grams of water? Use Table a .

Answer:______o 5. If there are 90g of sodium nitrate are in the container at 10 C, then how many grams of sodium nitrate will remain undissolved in 100 grams of water? Use Table a.

Answer:______o o 6. Raising the temperature of the mixture from 5 C to 20 C will change the amount of dissolved sodium nitrate by how much? Use Table a . Answer:______

7. What must the temperature be in order to dissolve the entire 85g sodium nitrate can be dissolved? Use Table a . Answer:______

Molarity(M) = Moles of Soute/Liter of Solution / Molality (m) = Moles of Solute/kilogram solvent

1. Sea water contains roughly 28.0 g of NaCl per liter. What is the molarity of sodium chloride in sea water?

2. What is the molarity of 245.0 g of H 2SO 4 dissolved in 1.00 L of solution?

3. What is the molarity of 5.30 g of Na 2CO 3 dissolved in 400.0 mL solution?

4. What is the molality of 5.00 g of NaOH in 750.0 g of water?

5. How many moles of Na 2CO 3 are there in 10.0 L of 2.0 M soluton?

6. How many moles of Na 2CO 3 are in 10.0 mL of a 2.0 M solution?

Milwaukie HS • Chemistry • Linman/ Herrington Name ______Period ___ Date ___/___/___ A602B Solutions: Molarity Calculations

1) How many grams of potassium carbonate are needed to make 200 mL of a 2.5 M solution?

2) How many liters of 4 M solution can be made using 100 grams of lithium bromide?

3) What is the concentration of a 450 mL solution that contains 200 grams of iron (II) chloride?

4) How many grams of ammonium sulfate are needed to make a 0.25 L solution at a concentration of 6 M?

5) What is the concentration of a solution that has a volume of 2.5 L and contains 660 grams of calcium phosphate?

6) How many grams of copper (II) fluoride are needed to make 6.7 liters of a 1.2 M solution? 7) How many liters of 0.88 M solution can be made with 25.5 grams of lithium fluoride?

8) What is the concentration of a solution that with a volume of 660. mL that contains 33.4 grams of aluminum acetate?

9) How many liters of 0.75 M solution can be made using 75 grams of lead (II) oxide?

10) How many grams of manganese (IV) oxide are needed to make a 5.6 liters of a 2.1 M solution?

11) What is the concentration of a solution with a volume of 9 mL that contains 2 grams of iron (III) hydroxide?

12) How many liters of 3.4 M solution can be made using 78 grams of isopropanol (C 3H8O)?

13) What is the concentration of a solution with a volume of 3.3 mL that contains 12 grams of ammonium sulfite?

Milwaukie HS • Chemistry • Linman/ Herrington Name ______Period ___ Date ___/___/___ D602 Dilutions Worksheet

1) If I have 340 mL of a 0.5 M NaBr solution, what will the concentration be if I add 560 mL more water to it?

2) If I dilute 250 mL of 0.10 M lithium acetate solution to a volume of 750 mL, what will the concentration of this solution be?

3) If I leave 750 mL of 0.50 M sodium chloride solution uncovered on a windowsill and 150 mL of the solvent evaporates, what will the new concentration of the sodium chloride solution be?

4) To what volume would I need to add water to the evaporated solution in problem 3 to get a solution with a concentration of 0.25 M? Milwaukie HS • Chemistry • Linman/ Herrington Name ______Period ___ Date ___/___/___ L601 Dilutions Lab During this activity you are going to perform a serial using a solution of the ionic compound potassium permanganate (KMnO 4). The KMnO 4 solution was created by adding 15.8 grams of KMnO4 to 1.00L of water thus creating a one-tenth molar (0.10M) solution of KMnO4.

1. Obtain a 12-well tray, a dropper, a beaker of water, toothpicks and a container of the one-part-per-hundred solution of KMnO4.

2. Put three or four drops of the KMnO4 solution into well one.

3. Put nine drops of water into each of the eleven remaining wells.

4. Now take the dropper and carefully transfer one drop of the KMnO 4 solution from well one into well two.

5. Use a toothpick (not the tip of the dropper!) to stir up well two. Observe what you see.

6. Record the new fraction of KMnO 4 to water, the new number of moles and the color density (in other words, what color of purple do you see? Or do you see any color at all?)

7. After you are done with well two carefully, wash the dropper. So no colored solution remains.

8. Repeat the dilution using the new solution in well two going from well two to well three. Fill in the data table

9. Continue the serial dilution all the way through to the last well making sure to carefully wash the dropper and stirring rod before making a transfer to the next well When you are finished, thoroughly wash the dropper and the well tray. Throw away the toothpicks in the trash.

Data: Well # 1 2 3 4 5 6 7 8 9 10 Fraction 1/10 Moles 0.1 Color Yes, Visible? Dark

Analysis: 1. What is the molarity of KMnO 4 in your last well?

2. What was the last well in which you could see any trace of the KMnO 4 dye?

3. Were there any KMnO4 molecules in the last well? How could you prove it?

Milwaukie HS • Chemistry • Linman/ Herrington Name ______Period ___ Date ___/___/___ A603 Solutions: Colligative Properties (FPD/BPE)

1. A saturated KCl solution at 10 oC will have how many grams of KCl dissolved in 100 grams of water?

Answer:______2. Raising the temperature of the mixture to 30 oC will increase the amount of dissolved KCl by how much?

Answer:______0 3. What would the boiling point of a 0.75 m BeF 2 solution be? K b(H 2O) = 0.51 C/m.

Answer:______

4. If I add 45 grams of sodium chloride to 500 grams of water, what will the melting and boiling points be of the resulting 0 0 solution? K b(H 2O) = 0.52 C/m and K f(H 2O) = 1.86 C/m.

Answer:______

5. What is the formula mass for a 1.33 g sample of solute in 55.99 g of water if the solution freezes at a temperature of - 1.9 0C.

6. Calculate the freezing and boiling points to a solution made using the following data: 24.92g AlCl 3 in 470.5g water

7.In general, will the addition of an electrolyte have a greater effect on the colligative properties of a solution than the addition on a nonelectrolyte will? Explain why or why not.

Milwaukie HS • Chemistry • Linman/ Herrington Name ______Period ___ Date ___/___/___ L602 Mass by Freezing Point

INTRODUCTION: The vapor pressure of a pure liquid at a given temperature is a characteristic property of that liquid. However, when a nonvolatile solute is dissolved in the liquid, the vapor pressure of the liquid is reduced. This lowering of the vapor pressure causes a change in the melting point, boiling point, and osmotic pressure of the liquid. The magnitude of the change in these properties depends upon the number of solute particles dissolved in a given amount of the solvent, but not upon the nature of the particles (their identity). Such properties are called colligative properties . The addition of ethylene glycol to the water in a car radiator in order to raise its boiling point or the use of salt to lower the melting point of ice on a sidewalk are some everyday applications of colligative properties.

In this experiment we will investigate the phenomenon of freezing-point depression and determine the molar mass of an unknown solute. The relationship between the lowering of the freezing point and the concentration of a solution is given by the following:

ΔTf = T f(pure solvent) - Tf(solution) = K f · m (1) where T f is the freezing temperature, K f is the molal freezing-point depression constant (a property of a given solvent), and m is the molality of solute in the solution. Molality of a solute is defined as follows:

m = moles of solute / kg of solvent (2)

One application of freezing-point depression is in the determination of the molar mass of an unknown solute. A weighed amount of the solute is dissolved in a known mass of solvent. The freezing point of the solvent (the temperature at which solid and liquid phases are in equilibrium) is determined by cooling the solution and plotting a graph of temperature as a function of time. A horizontal portion of the graph indicates that a pure liquid will freeze at a constant temperature. However, a solution will freeze over a range of temperatures and will not exhibit the constant freezing point of the pure liquid; instead of exhibiting a horizontal portion, the plot will show a change of slope when solid solvent begins to form. The concentration of dissolved solute then steadily increases as the solvent freezes, causing the freezing point to continually decrease. (The solid forming is pure solvent.) The temperature at which freezing begins is determined by the intersection of the two extrapolated straight lines. In practice, it is necessary to first determine the freezing point of the solvent alone, since the solvent may not be pure. This step also makes prior calibration of the thermometer unnecessary. With the change in freezing point and the value of K f, it is then possible to calculate the approximate molar mass of the solute.

The phenomenon of supercooling occurs when a liquid cools below its freezing point without crystallizing. A supercooled liquid is in an unstable condition, and any disturbance such as vibration will cause crystallization to begin, with a consequent rise in temperature to the actual freezing point. The dip in the graph due to supercooling should be ignored and the two straight portions extrapolated to their intersection to find the freezing point.

EQUIPMENT:: Thermometer 600 ml plastic beaker 50 ml flask

MATERIALS: Ice distilled water rock salt methanol(CH 3OH)

PROCEDURE:

Part 1.

1. Place 50.0 ml of distilled water in a 50-ml flask. Place about 250 ml of crushed ice in a 600-ml plastic beaker. Set the distilled water flask on the ice. Add more ice around the flask. On top of the ice layer about 50 ml of rock salt. Avoid getting any ice or salt in the flask.

2. Rotate the flask of distilled water to speed up the freezing process. When some ice has formed on the flask, measure the temperature of the distilled water. Record the freezing point of the distilled water in the date table.

Part 2.

3. Dry the flask. Place the flask on the balance and weight the flask on the balance. Record the mass of the flask in the data table. Add 50.0mL of distilled water to the flask and weight the flask containing the water… record the mass in the data table. Add between 1.00g and 1.10g of methanol to the flask. Weigh and record in the mass data table. Freeze the solution in the same manner as the distilled water. Record the freezing point of the solution in the data table.

Part Mass Empty Flask Mass Flask+Water Mass Flask+Water+Methanol Freezing Temperature 1. 2. CALCULATIONS AND CONCLUSIONS: 1. Calculate the freezing point depression mass of your solute using the following equations.

Answer:______2. Calculate the chart mass of your solute.

Answer:______3. Calculate the experimental error. E is from problem #1A is from problem #2

Answer:______4. Why is it important to determine the freezing point of your solvent?

5. Why must salt be placed in a hand-crank ice cream freezer?

6. What are some sources of error in this lab?

7. What is the formula mass for a 1.33 g sample of solute in 55.99 g of water if the solution freezes at a temperature 0 of -2.9 C ?

Answer:______8. Why will salt on an icy sidewalk make the sidewalk safer?

Milwaukie HS • Chemistry • Linman/ Herrington Name ______Period ___ Date ___/___/___ L603 Gravimetric Copper (II )Chloride OBJECTIVE : .Experimentally determine the of copper(II) chloride solution.

MATERIALS :. three ungalvanized nails, 8d balance one 18mmx185mm test tube test tube clamp copper(II)chloride solution HAZARDS : .Avoid skin contact when using Copper (II) Chloride solution.

INTRODUCTION : Molar concentration is defined as the number of moles of solute dissolved in a liter of solution, M=n/V. You have calculated the molar concentration of solutions based on the number of grams of solute dissolved in a given quantity of solution. In this lab you will measure out a given volume of copper(II) chloride solution. Therefore, you will have the volume (V) of the copper(II)chloride that you will using. However, you will not have the number of moles(n) of copper(II) chloride that is in the solution. You must experimentally determine the number of moles by reaction the copper(II) chloride with a common iron nail.

EXAMPLE CALCULATION: A 14.9ml sample of iron(III) chloride in a large test-tube was reacted with three clean copper nails having a total mass of 25.91grams. The nails and iron(III) chloride were agitated to speed up reaction. After the reaction, the nails were cleaned, dried and weighed. The mass after reaction was recorded as 24.02grams. a) Calculate the mass change of the copper nails. 25.91g -24.02g 1.89g b) Calculate the moles of copper consumed. 1.89g ÷63.5 g/mol=0.0298mol c) Calculate the number of moles of iron(III)chloride that reacted with the copper.

2FeCl 3 + Cu → 2FeCl 2 + CuCl 2 2FeCl 3 0.0298molCu x ------=0.0596 FeCl 3 mol 1m Cu d) Calculate molar concentration.

M=n/V M=(0.0596 FeCl 3 mol)/(0.0149L) M=4.00M FeCl 3

PROCEDURE 1) . Clean three new, ungalvanized, 8d, iron nails until they shine. 2) . Mass the three nails to the nearest 100 th of a gram and record the mass in the table. 3) . Obtain about 10 to 15 mL of copper(II) chloride solution; record the volume to three significant digits:______. 4) . Place the nails in the test tube, pour the copper(II) chloride solution in with the nails. 5) . Continuously swirl the test tube: this will keep fresh solution near the surface of the nails. 6) . Continue swirling until the solution is no longer blue-green. 7) . Pour the solution into a small beaker. Rinse and clean off all of the plated copper on the nail, using a paper towel. 8) . Dry and weigh the nails. Record this weight in the table. 9) . Pour the solution into the labeled recycle beaker. DO NOT POUR DOWN DRAIN!! 10) . Put used nails in beaker labeled "used nails".

DATA TABLE Mass of nails Before After

CALCULATIONS & QUESTIONS: 1) Write the balanced chemical reaction of solid iron reacts with copper(II) chloride solution to form iron(II) chloride solution and copper solid .

2) Calculate the mass change of the iron nails.

3) Calculate the moles of iron consumed .

4) Calculate the moles of Copper (II) Chloride that reacted with the iron.

5) Calculate the molar concentration of the Copper (II) Chloride solution.

6) If you had added water to your Copper (II) Chloride solution prior to adding the nails, would this have altered your reaction? How? (Explain)

Milwaukie HS • Chemistry • Linman/ Herrington Name ______Period ___ Date ___/___/___ A604 Molarity, Molality and Colligative Properties

The molarity of a solution is the number of moles of solute per liter of solution. The symbol for molarity is M. Thus a 3.0 molar solution of nitric acid, abbreviated 3.0 M HNO 3, contains 3.0 moles of HNO 3 per liter of solution.

Sample problem #1: What mass of sodium hydroxide, NaOH, is required to prepare 3.00 liters of 0.25 M solution ?

Solution: given volume of solution and molarity of solution find the mass of solute.

3.00 liters 0.25 moles NaOH 40.0 g NaOH = 30.0 g NaOH 1 liter 1 mole NaOH

Sample Problem #2: What volume of 1.25 M NaOH can be prepared using 60.0g of sodium hydroxide?

Solution: given mass of solute and molarity of solution find the volume of solution

60.0 g NaOH 1 mole NaOH 1 liter soln = 1.2 Liters of soln 40.0 g NaOH 1.25 moles NaOH

Molarity Problems (moles / liter of solution)

1) Calculate the molarity, M, of the following solutions: a) 1.5 moles of NaC 2H3O2 dissolved in 750 ml of solution. b) 3.00 moles of H 2SO 4 dissolved in 1250 ml of solution. c) 66 grams of NaC 2H3O2 dissolved in 500 ml of solution. d) 68.4 g of glucose, C 6H12 O6 in 500 ml of water solution. 2) What is the molarity of a solution that contains 125 g CH 3OH in 0.25 L of solution? 3) What is the molarity of a solution that contains 85.0 grams of Na 2SO 4 in 325 ml of solution? 4) What is the molarity of a solution that contains 210 grams of Al 2(SO 4)3 in 2.75 liters of solution?

Solve for mass:

5) Determine the grams of solute required to prepare the following solutions: a) 1500 ml of 3M KOH b) 750 ml of a 0.50 M solution of HC 2H3O2 c) 2 liters of a 2.5 M solution of C6H12 O6 d) 250 ml of a 1.25 M solution of NaCl 6) What mass of K 3PO 4 is required to prepare 4.00 liters of 1.50M solution? 7) What mass of CH 3OH is required to prepare 1.50 liters of 3.00M solution? Solve for volume: 8) What volume of 0.750 M solution can be prepared using 90.0 grams of NH 4Cl? 9) If a 0.75 M solution of NaOH is to be prepared using 18.5 g NaOH, how many ml of solution can be produced? 10) What volume of 1.40 M HC 2H3O2 solution contains 0.400 mole of HC 2H3O2? The molality of a solution is the moles of solute dissolved in 1 kilogram (1000g) of solvent (often water). The symbol for molality is lower case “m”. Thus a 3.0 molal solution of nitric acid, abbreviated 3.0 m HNO 3, contains 3.0 moles of HNO 3 in 1 kg of water. MOLAL PROBLEMS (moles / kg of solvent )

11) How many grams of AgNO 3 are needed to prepare a 0.125 m solution in 250 grams of water?

12) What mass in grams of sucrose, C 6H12 O6, must be dissolved in 2000 grams of water to make a 0.1 molal solution?

13) Determine the molality (m) of a solution containing 42 grams of glycerin, C 3H5(OH) 3 in 750 grams of water.

14) A solution contains 85.0 grams of methanol, CH 3OH, in 3000 grams of water. Calculate the molality of the solution.

FREEZING POINT DEPRESSION AND BOILING POINT ELEVATION (for water B.P. elevation const. = 0.512 oC/m, F.P. depression const. = 1.86 oC/m)

15) A solution contains 15 grams of sucrose, C 12H22 O11 , in 250 grams of water. What is the freezing point of the solution? (determine the molality first)

16) What is the boiling point of the solution in problem 15 above?

17) Calculate the boiling point and freezing point of a solution that contains 30.0 grams of acetic acid, HC 2H3O2, dissolved in 250 grams of water.

18) Calculate the freezing point of a solution containing 5.70 grams of sugar, C 12 H22 O11 , in 50 grams of water.

19) Calculate the boiling point of the sugar solution in problem 18 above.

20) Calculate the freezing point of a solution containing 60. grams of NaOH in 500 grams of water.

21) Calculate the boiling point of the solution in the above problem.

22) How many grams of ethanol, CH 3OH, must be dissolved in 500 grams of water to lower the freezing point to -6.51 oC?

Extra credit: How many grams of ethylene glycol, C 2H4(OH) 2, must be dissolved in 200 grams of water to lower the freezing point to -29.75 oC? If the density of ethylene glycol is 1.12 g/ml, how many milliliters of ethylene glycol are required?