TOPICS TO BE COVERED 1. WHAT ARE SOLUTIONS? 2. SOLVENTS AND SOLUTES 3. SOLUBILITY AND ITS FACTORS 4. CONCENTRATIONS 5. SOLUTION STOICHIOMETRY 6.

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1 TOPICS TO BE COVERED 1. WHAT ARE SOLUTIONS? 2. SOLVENTS AND SOLUTES 3. SOLUBILITY AND ITS FACTORS 4. CONCENTRATIONS 5. SOLUTION STOICHIOMETRY 6. COLLIGATIVE PROPERTIES

2 SOLUTIONS CHEMICALS + WATER

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4 1. WHAT ARE SOLUTIONS OBJECTIVE: WHAT ARE THEY?

5 SOLUTIONS IMPORTANCE OF STUDYING SOLUTIONS BECAUSE MANY REACTIONS TAKE PLACE IN SOLUTIONS BECAUSE MIXING REACTANTS IN SOLID FORM OFTEN DO NOT RESULT IN REACTIONS. REACTIONS REQUIRE COLLISIONS AT THE ATOMIC/MOLECULAR LEVEL, AND IN THE SOLID STATE, THIS DOES NOT OCCUR AT A SIGNIFICANT RATE.

6 1. WHAT ARE SOLUTIONS? SOLUTIONS ARE HOMOGENOUS MIXTURES HOMOGENOUS VS. HETEROGENEOUS MIXTURE VS. COMPOUND

7 1. WHAT ARE SOLUTIONS Does not always involve liquids

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10 1. WHAT ARE SOLUTIONS SOLVENT - PRESENT IN GREATER AMOUNT - DOES THE DISSOLVING SOLUTE - PRESENT IN LESSER AMOUNT - IS THE ONE DISSOLVED WATER IS THE UNIVERSAL SOLVENT

11 1. WHAT ARE SOLUTIONS IF A SOLUTION IS A MIXTURE, DO THE SOLUTES AND THE SOLVENTS CHEMICALLY REACT OR PHYSICALLY MIX?

12 2. SOLUBILITY OBJECTIVE: IF SOMETHING DOES OR DOES NOT DISSOLVE

13 2. SOLUBILITY Why do some things dissolve while others do not? What does it mean for something to dissolve?

14 2. SOLUBILITY What does it mean for something to dissolve?

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16 2. SOLUBILITY Why do some things dissolve while others do not? Like dissolves Like

17 2. SOLUBILITY Like dissolves Like Polar Solvent will dissolve Non-Polar Solvent will dissolve

18 2. SOLUBILITY Miscible vs. Immiscible Miscible = dissolves Immiscible = does NOT dissolve

19 2. SOLUBILITY How much of some thing can be dissolved? Solubility THE MAXIMUM AMOUNT OF A SOLUTE THAT CAN DISSOLVE AT A SPECIFIED TEMPERATURE AND PRESSURE

20 2. SOLUBILITY Increasing/Decreasing Solubility 1. Temperature 2. Pressure

21 SO AS TEMPERATURE, SOLUBILITY

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29 2. SOLUBILITY Increasing/Decreasing Solubility with Temperature

30 Unsaturated Solutions more solute can be dissolved no heat necessary

31 Saturated Solutions no more solute can be dissolved no heat necessary

32 Super-Saturated Solutions more solute than normal heat necessary

33 Super-Saturated Solutions Rock Candy

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35 SOLUBILITY OF GASES AS TEMPERATURE THE SOLUBILITY OF GAS. SO TEMPERATURE AND SOLUBILITY OF A GAS HAVE A(N). RECALLING HEAT AS KINETIC ENERGY, WE CAN EXPLAIN THIS BY

36 SOLUBILITY OF SOLIDS SOLUBILITY OF GASES

37 SUMMARY & REVIEW 1. EXPLAIN WHY THERE MIGHT BE MORE MINERAL FORMATION SURROUNDING THERMAL SPRINGS THAN COOL MOUNTAIN SPRINGS. 2. WHY DOES WARM SODA FLATTEN QUICKER THAN COLD SODA?

38 3. CONCENTRATIONS OBJECTIVE: MEASURING SOLUBILITY

39 3. CONCENTRATIONS concentration = how much solute in the solution 2 methods

40 Symbol Formula 3. CONCENTRATIONS Molarity MOLALITY Units Example

41 3. CONCENTRATIONS Molarity MOLALITY Symbol Formula M M = mol L Units mol = mol of SOLUTE L = liters of solution Example 5 M, or 5 molar

42 3. CONCENTRATIONS 1.23 mol of HCl in solution With volume of 5.00 L. What is molartiy?

43 3. CONCENTRATIONS 3.45 M solution of AgCl is made with mol of AgCl. What is volume?

44 3. CONCENTRATIONS 3.45 M solution of AgCl is made with 2.45 L. What is mol of AgCl?

45 3. CONCENTRATIONS Precipitate = a solid that forms

46 3. CONCENTRATIONS L of M HCl is added to Zn. What mass of ZnCl 2 is formed? Zn + 2HCl ZnCl 2 + H 2

47 3. CONCENTRATIONS 11.0 g of Cu are needed. What volume of a M solution of CuSO is needed to result in 11.0 g 4 of copper? CuSO 4 + Fe Cu + FeSO 4

48 Ba(NO 3 ) 2(aq) + Na 2 SO 4(aq) Ba(SO 4 ) (s) + 2NaNO 3(aq) 25mL of 0.5M Ba(NO 3 ) 2 solution is combined with excess Na 2 SO 4. How many grams of precipitate formed?

49 Pb(NO 3 ) 2(aq) + 2NaCl (aq) PbCl 2(s) + 2NaNO 3(aq) How many grams of precipitate would form if 30mL of a 0.25M Pb(NO 3 ) 2 solution was added to 20mL of a 0.50M NaCl solution? How many moles of the excess reactant are left over after the reaction? What is the molarity of the excess reactant after the reaction?

50 CaCl 2(aq) + 2NH 4 OH (aq) Ca(OH) 2(s) + 2NH 4 Cl (aq) What volume of a 0.2M NH 4 OH solution would be required to precipitate all of the Ca 2+ ions in 50mL of a 0.15M CaCl 2 solution?

51 SOLUBILITY OF GASES HENRY S LAW IF THE SOLUBILITY OF A GAS IN WATER IS 0.77G/L AT 350KPA OF PRESSURE, WHAT IS ITS SOLUBILITY, IN UNITS OF GRAMS/LITER, AT 100KPA?

52 SOLUBILITY OF GASES HENRY S LAW A GAS HAS A SOLUBILITY OF 3.6G/L AT A PRESSURE OF 100KPA. WHAT PRESSURE IS NEEDED TO PRODUCE AN AQUEOUS SOLUTION CONTAINING 9.5G/L OF THE SAME GAS? THE SOLUBILITY OF METHANE IN WATER AT 100KPA IS 0.026G/L, WHAT WILL THE SOLUBILITY BE AT A PRESSURE OF 180KPA?

53 SOLUBILITY OF LIQUIDS LIKE DISSOLVES LIKE MISCIBLE NON-POLAR AND NON-POLAR = MISCIBLE POLAR + POLAR = MISCIBLE IMMISCIBLE

54 PERCENT SOLUTIONS SIMILAR TO PPM

55 PERCENT SOLUTIONS WHAT IS THE PERCENT BY VOLUME OF ETHANOL (C 2 H 6 O) WHEN 75ML OF ETHANOL IS DILUTED TO A VOLUME OF 250ML WITH WATER? A SOLUTION CONTAINS 2.7G OF CUSO4 IN 75ML OF SOLUTION. WHAT IS THE PERCENT BY MASS OF THE SOLUTION?

56 CONCENTRATION OF IONS CALCULATE THE NUMBER OF MOLES OF CL- IN 2.75 L OF 1.0X10-3M ZNCL2 HOW MANY GRAMS OF SULFATE ION ARE PRESENT IN 500ML OF A 2M AL2(SO4)3 SOLUTION?

57 5. COLLIGATIVE PROPERTIES OBJECTIVE: HOW ADDING THINGS TO WATER CHANGES WATER

58 5. COLLIGATIVE PROPERTIES MAIN IDEA: The properties of a solution are different from those of a pure solvent. When you add things, like solutes, to water, it changes the properties of the water!

59 SOME OF THESE DIFFERENCES ARE DUE TO THE PRESENCE OF SOLUTE PARTICLES IN THE SOLUTION.

60 5. COLLIGATIVE PROPERTIES COLLIGATIVE PROPERTIES = A PROPERTY OF A SOLUTION THAT DEPENDS ON THE CONCENTRATION OF THE SOLUTE PARTICLES.

61 5. COLLIGATIVE PROPERTIES COLLIGATIVE PROPERTIES = 1. Increases boiling temperature 2. Lowers freezing temperature

62 COLLIGATIVE PROPERTIES COLLIGATIVE PROPERTIES A PROPERTY OF A SOLUTION THAT DEPENDS ON THE CONCENTRATION OF THE SOLUTE PARTICLES. THE WORD COLLIGATIVE IS DERIVED FROM THE LATIN COLLIGATUS MEANING BOUND TOGETHER, SINCE THESE PROPERTIES ARE BOUND TOGETHER BY THE FACT THAT THEY ALL DEPEND ON THE NUMBER OF SOLUTE PARTICLES.

63 COLLIGATIVE PROPERTIES BOILING POINT ELEVATION THE DIFFERENCE IN TEMPERATURE BETWEEN THE BOILING POINTS OF A SOLUTION AND OF THE PURE SOLVENT. FREEZING POINT DEPRESSION IS THE DIFFERENCE IN TEMPERATURE BETWEEN THE FREEZING POINTS OF A SOLUTION AND OF THE PURE SOLVENT.

64 Symbol Formula 4. CONCENTRATION Molarity MOLALITY Units Example

65 4. Molarity CONCENTRATIONMOLALITY Symbol M m Formula Units M = mol L mol = mol of SOLUTE L = liters of solution m = mol kg mol = mol of SOLUTE kg = kilograms of SOLVENT Example 5 M, or 5 molar 5 m, or 5 molal

66 5. COLLIGATIVE PROPERTIES How many grams of KI must be dissolved in g of water to produce a molal KI solution?

67 5. COLLIGATIVE PROPERTIES 1. Determine the molality of a solution of 560 g acetone, C 3 H 6 O in kg of water. 2. What is the molality of a solution of 12.9 g of fructose, C 6 H 12 O 6, in 31 g of water? 3. Determine the molal concentration of 71.5 g of linoleic acid, C 18 H 32 O 2, dissolved in 525 g of C 6 H How many moles of butanol, C 4 H 10 O must be dissolved in kg of ethanol in order to produce a 12.0 m solution? 5. Convert the answer above to grams! 6. What mass of urea, NH 2 CONH 2, must be dissolved in 2250 g of water to make a 1.50 molal solution? 7. What mass of CaCl 2 must be dissolved in g of water to produce 0.82 molal solution?

68 5. COLLIGATIVE PROPERTIES 1. Determine the molality of a solution of 560 g acetone, C 3 H 6 O in kg of water. 2. What is the molality of a solution of 12.9 g of fructose, C 6 H 12 O 6, in 31 g of water? 3. Determine the molal concentration of 71.5 g of linoleic acid, C 18 H 32 O 2, dissolved in 525 g of C 6 H How many moles of butanol, C 4 H 10 O must be dissolved in kg of ethanol in order to produce a 12.0 m solution? 5. Convert the answer above to grams! 6. What mass of urea, NH 2 CONH 2, must be dissolved in 2250 g of water to make a 1.50 molal solution? 7. What mass of CaCl 2 must be dissolved in g of water to produce 0.82 molal solution?

69 COLLIGATIVE PROPERTIES THE MAGNITUDE OF BP ELEVATION AND FP DEPRESSIONS IS PROPORTIONAL TO THE NUMBER OF SOLUTE PARTICLES DISSOLVED IN THE SOLVENT.

70 COLLIGATIVE PROPERTIES WOULD A DILUTE OR CONCENTRATED SODIUM FLUORIDE SOLUTION HAVE A HIGHER BOILING POINT? IF EQUAL NUMBER OF MOLES OF KI AND MGF 2 ARE DISSOLVED IN EQUAL AMOUNTS OF WATER, WHICH SOLUTION WOULD HAVE THE HIGHEST: BOILING POINT FREEZING POINT

71 MOLARITY MOLALITY VOLUME OF SOLUTE + VOLUME OF SOLVENT UNIT = M MASS OF SOLVENT IN KILOGRAMS UNIT = M (ITALICIZED) BOTH MOLARITY AND MOLALITY MEASURE

72 CALCULATING MOLALITY CALCULATE THE MOLALITY AND TOTAL MOLALITY (IF APPLICABLE) OF A SOLUTION PREPARED BY DISSOLIVING 10.0G OF NACL IN 600 G OF WATER. CALCULATE THE MOLALITY AND TOTAL MOLALITY (IF APPLICABLE) OF A SOLUTION PREPARED BY DISSOLIVING 10.0G C 12 H 22 O 11 OF IN 600 G OF WATER.

73 CALCULATING MOLALITY HOW MANY GRAMS OF POTASSIUM IODIDE MUST BE DISSOLVED IN G OF WATER TO PRODUCE A MOLAL KI SOLUTION?

74 CALCULATING MOLALITY WHAT IS THE DIFFERENCE BETWEEN A 1M AND A 1M SOLUTION? A 4 G SUGAR CUBE (C 12 H 22 O 11 ) IS DISSOLVED IN A 350 ML TEACUP OF 80 C WATER. WHAT IS THE MOLALITY OF THE SUGAR SOLUTION IF THE DENSITY OF WATER AT 80 = G/ML

75 CALCULATING BP AND FP CHANGES BP ΔT B = K B * M FP ΔT F = K F * M

76 CALCULATING BP AND FP CHANGES K B, K F = THE MOLAL BP/FP CONSTANT, WHICH IS EQUAL TO THE CHANGE IN BP/FP TEMPERATURE FOR A 1 MOLAL SOLUTION.

77 CALCULATING BP AND FP CHANGES WHAT IS THE BOILING POINT OF A 1.5 MOL SOLUTION THAT IN 800G OF WATER?

78 CALCULATING BP AND FP CHANGES WHAT IS THE BOILING POINT OF A 1.2 MOL SOLUTION OF NACL IN 800G OF WATER?

79 CALCULATING BP AND FP CHANGES WHAT IS THE BP AND FP OF A 1.40 MOL SOLUTION OF NA 2 SO 4 IN 1750G OF WATER?

80 DETERMINING MOLAR MASS FROM ΔT B AND ΔT F MOLAR MASS = 7.5 G OF SOLUTE IS ADDED TO G OF WATER. THE WATER BOILS AT DEGREES C. WHAT IS THE MOLAR MASS OF THE SOLUTE?

81 DETERMINING MOLAR MASS FROM ΔT B AND ΔT F WHAT INFORMATION/MEASUREMENTS ARE NEEDED TO FIND THE MOLAR MASS OF A SOLUTE WHEN GIVEN THE BOILING POINT ELEVATION, ΔT B, FOR AN AQUEOUS SOLUTION?

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