Chapter 8 Solutions PDF

Chapter 8 Solutions  Chapter 8 Chapter Outline 8.1Characteristics of solutions 8.2Solubility 8.3Solution formation 8.4Solubility rules 8.5Percent concentration units 8.6Molarity concentration unit 8.7Diluti...

Chapter 8 Solutions  Chapter 8 Chapter Outline 8.1Characteristics of solutions 8.2Solubility 8.3Solution formation 8.4Solubility rules 8.5Percent concentration units 8.6Molarity concentration unit 8.7Dilution 8.8Colloidal dispersions and suspensions 8.9Colligative properties of solutions 8.10Osmosis and osmotic pressure Copyright ©2016 Cengage Learning. All Rights Reserved. 2  Section 8.1 Characteristics of Solutions Solution A homogeneous mixture of two or more substances with each substance retaining its own chemical identity Components of a solution: – Solvent: Component of a solution that is present in the greatest amount – Solute: Component of a solution that is present in a lesser amount relative to that of the solvent Substance being dissolved Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 3  Section 8.1 Characteristics of Solutions Figure 8.1 - Colored Crystals (Solute) Mixed with Water (Solvent) Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 4  Section 8.2 Solubility What is Solubility? The maximum amount of solute that will dissolve in a given amount of solvent under a given set of conditions How Solubility and Dissolving Work Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 5  Section 8.1 Characteristics of Solutions What are Some Things that Affect Solubility? Return to TOC Copyright © Cengage Learning. All rights reserved 6  Section 8.2 Solubility Effect of Temperature on Solubility Most solids become more soluble in water with increasing temperature Not True for Gasses! In contrast, gas solubilities in water decrease with increasing temperature Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 7  Section 8.2 Solubility Table 8.1 - Solubilities of Various Compounds (Solids) in Water at 0°C, 50°C, and 100°C Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 8  Section 8.2 Solubility Effect of Pressure on Solubility Pressure has little effect on the solubility of solids and liquids in water Not True for Gasses! Kramer buys half a can of soda Pressure has major effect on the solubility of gases in water Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 9  Section 8.2 Solubility Henry’s Law The amount of gas that will dissolve in a liquid at a given temperature is directly proportional to the partial pressure of the gas above the liquid. – As the pressure of a gas above the liquid increases, the solubility of the gas increases, and vice versa Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 10  Section 8.1 Characteristics of Solutions Return to TOC Copyright © Cengage Learning. All rights reserved 11  Section 8.1 Characteristics of Solutions Return to TOC Copyright © Cengage Learning. All rights reserved 12  Section 8.2 Solubility Unsaturated Solution A solution that contains less than the maximum amount of solute that can be dissolved under the conditions at which the solution exists – Most commonly encountered solutions fall into this category Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 13  Section 8.2 Solubility Saturated Solution A solution that contains the maximum amount of solute that can be dissolved under the conditions at which the solution exists Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 14  Section 8.2 Solubility Supersaturated Solution An unstable solution that temporarily contains more dissolved solute than that present in a saturated solution – Excess solute crystallizes out with time and the solution reverts to a saturated solution Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 15  Section 8.1 Characteristics of Solutions Return to TOC Copyright © Cengage Learning. All rights reserved 16  Section 8.2 Solubility (Goldfarb, Patent Pending) Return to TOC Copyright © Cengage Learning. All rights reserved 17  Section 8.2 Solubility Concentrated and Dilute Solutions Concentrated solution: A solution that contains a large amount of solute relative to the amount that could dissolve Dilute solution: A solution that contains a small amount of solute relative to the amount that could dissolve Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 18  Section 8.2 Solubility Figure 8.4 - Concentrated and Dilute Solutions Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 19  Section 8.2 Solubility Aqueous and Nonaqueous Solutions Aqueous solution: A solution in which water is the solvent Nonaqueous solution: A solution in which a substance other than water is the solvent Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 20  Section 8.3 Solution Formation For a Solute to Dissolve in a Solvent Two types of interparticle attractions must be overcome (broken): – Attractions between solute particles (solute–solute attractions) – Attractions between solvent particles (solvent– solvent attractions) New type of interaction arises – Attraction between solute and solvent particles (solute–solvent attractions) Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 21  Section 8.4 Solubility Rules In general, it is found that the greater the difference in solute–solvent polarity, the less soluble is the solute Substances of like polarity tend to be more soluble in each other than substances that differ in polarity – “Like dissolves like” (but not in all cases) Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 22  Section 8.5 Percent Concentration Units Concentration The amount of solute present in a specified amount of solution Three methods of expressing concentration: – Percent concentration – Molarity concentration – Molality Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 23  Section 8.5 Percent Concentration Units Percent Concentration Three different ways of representing percent concentration: – Percent by mass (mass–mass percent) – Percent by volume (volume–volume percent) – Mass–volume percent Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 24  Section 8.5 Percent Concentration Units Percent by Mass mass of solute Percent by mass = × 100 mass of solution This is always the total mass. Mass of solution = mass of solute + mass of solvent Solution = solute + solvent Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 25  Section 8.5 Percent Concentration Units A solution having a mass percent concentration of 10% contains: a.10 g of solute and 90 g of solvent. b.10 g of solvent and 10 g of solute. c.10 g of solute per 100 g of solvent. d.10 g of solvent per 100 g of solute. 10 g solute 100 = 10% 10 g solute + 90 g solvent X Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 26  Section 8.5 Percent Concentration Units Exercise What is the percent by mass concentration of glucose in a solution made by dissolving 5.5 g of glucose in 78.2 g of water? Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 27  Section 8.5 Percent Concentration Units Exercise What is the percent by mass (m/m) concentration of glucose in a solution made by dissolving 5.5 g of glucose in 78.2 g of water? 5.5 g 100 6.6% = 5.5 g + 78.2 g Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 28  Section 8.5 Percent Concentration Units Percent by Volume (v/v) This is always the total volume Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 29  Section 8.5 Percent Concentration Units Exercise Calculate the volume percent (v/v) of solute of 30.0 mL of methyl alcohol in enough water to give 435 mL of solution. 30.0 mL 100 6.90% = 435 mL This is always the total volume. Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 30  Section 8.5 Percent Concentration Units Mass–Volume Percent mass of solute g  Mass – volume percent = × 100 volume of solution mL  This is always the total volume Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 31  Section 8.5 Percent Concentration Units Table 8.3 - Conversion Factors Obtained From Percent Concentration Units Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 32  Section 8.5 Percent Concentration Units How many grams of sodium chloride are needed to prepare 150 mL of 0.9% (m/v) sodium chloride? a.135 g b.13.5 g c.1.35 g d.0.135 g Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 33  Section 8.5 Percent Concentration Units How many grams of sodium chloride are needed to prepare 150 mL of 0.9% (m/v) sodium chloride? a.135 g 0.9 g Xg b.13.5 g = 100 mL 150 mL c.1.35 g d.0.135 g Or 0.009 x 150 mL = 1.35 ml = 1.35 g b/x density of water is 1 g/mL Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 34  Section 8.6 Molarity Concentration Unit Molarity Moles of solute in a solution divided by the liters of solution moles of solute Molarity M  = liters of solution Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 35  Section 8.6 Molarity Concentration Unit Exercise You have 1.00 mol of sugar in 125.0 mL of solution. Calculate the concentration in units of molarity. Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 36  Section 8.6 Molarity Concentration Unit Exercise You have 1.00 mol of sugar in 125.0 mL of solution. Calculate the concentration in units of molarity. 8.00 M Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 37  Section 8.6 Molarity Concentration Unit Exercise You have a 10.0 M sugar solution. What volume of this solution do you need to have 2.00 mol of sugar? Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved.  Section 8.6 Molarity Concentration Unit Exercise You have a 10.0 M sugar solution. What volume of this solution do you need to have 2.00 mol of sugar? 0.200 L 10 mol = 2 mol L x Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved.  Section 8.6 Molarity Concentration Unit Exercise Consider separate solutions of NaOH and KCl made by dissolving 100.0 g of each solute in 250.0 mL of solution. Calculate the molar (moles/L) concentration of each solution. Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 40  Section 8.6 Molarity Concentration Unit Exercise Consider separate solutions of NaOH and KCl made by dissolving 100.0 g of each solute in 250.0 mL of solution. Calculate the molar concentration of each solution. 10.0 M NaOH 5.37 M KCl 100 g 1 mol X = 10.02 mol/L = M 0.25 L 39.9 g Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 41  Section 8.7 Dilution How would you prepare 100 mL of 0.9% saline solution in water from a 10% saline solution? a.90 mL of 10% saline solution + 100 mL of water b.90 mL of 10% saline solution + 10 mL of water c.9 mL of 10% saline solution + 100 mL of water d.9 mL of 10% saline solution + 91 mL of water Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 42  Section 8.7 Dilution The process in which more solvent is added to a solution in order to lower its concentration  Concentration of   volume of   concentration of   volume of    ×  =  ×   stock solution   stock solution   diluted solution   diluted solution  Cs × Vs = Cd × Vd Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 43  Section 8.7 Dilution How would you prepare 100 mL of 0.9% saline solution in water from a 10% saline solution? a.90 mL of 10% saline solution + 100 mL of water b.90 mL of 10% saline solution + 10 mL of water c.9 mL of 10% saline solution + 100 mL of water d.9 mL of 10% saline solution + 91 mL of water Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 44  Section 8.7 Dilution Concept Check A 0.50 M solution of sodium chloride sits on a lab bench. Which of the following would decrease the concentration of the salt solution? a) Add water to the solution. b) Pour some of the solution down the sink drain. c) Add more sodium chloride to the solution. d) Let the solution sit out in the open air for a couple of days. e) At least two of the above would decrease the concentration of the salt solution. Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 45  Section 8.7 Dilution Exercise What is the minimum volume of a 2.00 M NaOH solution needed to make 150.0 mL of a 0.800 M NaOH solution? Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 46  Section 8.7 Dilution Exercise What is the minimum volume of a 2.00 M NaOH solution needed to make 150.0 mL of a 0.800 M NaOH solution? 60.0 mL c Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 47  Section 8.1 Characteristics of Solutions Molality Return to TOC Copyright © Cengage Learning. All rights reserved 48  Section 8.1 Characteristics of Solutions Unlike molarity, molality is temperature independent. Since, temperature can cause liquid to Contract or expand, molarity is temperature dependent. *unit is lower case m! Return to TOC Copyright © Cengage Learning. All rights reserved 49  Section 8.7 Dilution Osmosis (Water diffusion Across a membrane) and Diffusion (Gasses) Return to TOC Copyright © Cengage Learning. All rights reserved 50  Section 8.10 Osmosis and Osmotic Pressure Osmosis Movement of high concentration of solvent (water) to low concentration, until equilibrium is reached – Semi-permeable membrane: A membrane that allows certain types of molecules to pass through it but prohibits the passage of other types of molecules Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 51  Section 8.10 Osmosis and Osmotic Pressure Figure 8.14 - An Illustration of a Semi-Permeable Membrane Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 52  Section 8.1 Characteristics of Solutions Osmosis: water moves from high concentration Of water (low solute concen.) to low water Concentration (high solute concen.) Low concentration Of water High concentration Of water Return to TOC Copyright © Cengage Learning. All rights reserved 53  Section 8.10 Osmosis and Osmotic Pressure High concentration Of water https://www.slideserve.com/cullen/remember Return to TOC Copyright © Cengage Learning. All rights reserved 54  Section 8.10 Osmosis and Osmotic Pressure Osmotic Pressure The pressure that must be applied to prevent the net flow of solvent through a semipermeable High concentration membrane from a Of water solution of lower solute concentration to a solution of higher solute concentration Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 55  Section 8.1 Characteristics of Solutions Return to TOC Copyright © Cengage Learning. All rights reserved 56  Section 8.1 Characteristics of Solutions Return to TOC Copyright © Cengage Learning. All rights reserved 57  Section 8.1 Characteristics of Solutions Tonicity: The ability of an extracellular solution to make water move into or out of a cell by osmosis is known as its tonicity. 1. Hypotonic Solutions 2. Hypertonic Solutions 3. Isotonic Solutions Return to TOC Copyright © Cengage Learning. All rights reserved 58  Section 8.10 Osmosis and Osmotic Pressure Hypotonic Solution A solution with a lower concentration of solutes (this means it has a higher water concentration) Water will move From its high concentration On the outside to its lower Concentration inside the cell Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 59  Section 8.10 Osmosis and Osmotic Pressure Hypertonic Solution A solution with a higher concentration of solutes (this means it has a lower water concentration) Water will move From its high concentration On the inside to its lower Concentration on the outside Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 60  Section 8.10 Osmosis and Osmotic Pressure Isotonic Solution A solution with equal solute concentration of cells No net flow of water in or Out of cell. Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 61  Section 8.10 Osmosis and Osmotic Pressure Figure 8.17 - Effects of Bathing Red Blood Cells in Various Types of Solutions Water moves in. Water moves out. No net flow of water. Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 62  Section 8.1 Characteristics of Solutions IV Fluid Types (start at 5:30) Return to TOC Copyright © Cengage Learning. All rights reserved 63  Chapter 8 Concept Question 1 How would you prepare 200 mL of a 0.8 M sodium hydroxide, molar mass = 40 g/mole, solution in water? Identify the solute and solvent. a.Add 64 g of sodium hydroxide to 200 mL of water. The solvent is water, and the solute is sodium hydroxide. b.Add 64 g of sodium hydroxide to 200 mL of water. The solvent is sodium hydroxide, and the solute is water. c.Add 6.4 g of sodium hydroxide to 200 mL of water. The solvent is water, and the solute is sodium hydroxide. d.Add 6.4 g of sodium hydroxide to 200 mL of water. The solvent is sodium hydroxide, and the solute is water. Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 64  Section 8.1 Characteristics of Solutions 40 g 0.8 mole 0.2 L 6.4 g mole x 1L x = Return to TOC Copyright © Cengage Learning. All rights reserved 65  Chapter 8 Concept Question 1 How would you prepare 200 mL of a 0.8 M sodium hydroxide, molar mass = 40 g/mole, solution in water? Identify the solute and solvent. a.Add 64 g of sodium hydroxide to 200 mL of water. The solvent is water, and the solute is sodium hydroxide. b.Add 64 g of sodium hydroxide to 200 mL of water. The solvent is sodium hydroxide, and the solute is water. c.Add 6.4 g of sodium hydroxide to 200 mL of water. The solvent is water, and the solute is sodium hydroxide. d.Add 6.4 g of sodium hydroxide to 200 mL of water. The solvent is sodium hydroxide, and the solute is water. Return to TOC Copyright ©2016 Cengage Learning. All Rights Reserved. 66