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Aim: Using Table F to Predict Solubility. Table F gives us information on the solubility of various compounds in solution You can predict the solubility of a compound or of the two products of a double replacement reaction. Recognizing & Understanding Double Replacement Reactions.
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Aim: Using Table F to Predict Solubility • Table F gives us information on the solubility of various compounds in solution • You can predict the solubility of a compound or of the two products of a double replacement reaction
Recognizing & Understanding Double Replacement Reactions • Double reactions contain 2 ionic compounds • Not every potential double replacement reaction will occur • 3 situations that ensure a DR reaction occurs: • One of the products is a solid (a precipitate) • One of the products is a gas • A molecular substance such as water is formed
3 Possible Outcomes of Double Replacement • One of the products must be: • A solid • A gas • A molecular compound, like water
Predicting Solubility with Table F Directions • Circle the symbol of the first ion or element • Underline the symbol of the second ion or element • Switch them around • Use Table F to predict the solubility
Predicting Double Replacement Products & Solubility • KI + Pb(NO3)2 + • 1. Predict products: reactants swap places • 2. Determine solubility of products • Example: For the reaction between LiBr and BaNO3, predict the products and determine their solubility
Homework • Complete page 11 of the packet
Aim: What are some factors that affect solubility? • Do Now: packet page 12
Dissolving Demo • Styrofoam • Salt • Sugar
Unequal Solubilities • Not all solutes dissolve to the same extent in the same solvent • Examples: • NaNO3: 125g/100g water at 60° C • NaCl: ~39g/100g water at 60° C
Factors Affecting Solubility • Temperature • Pressure • Particle size • Nature of the solute & solvent (polarity)
Solubility Factors: Temperature • Solids: as temp , solubility • Liquids: as temp , solubility • Gas: as temp , solubility
Solubility Factors: Pressure • Solids: as pressure , no effect • Liquids: as pressure , no effect • Gas: as pressure , solubility Applying principles of solubility and pressure, explain why soda goes flat when you open the can.
Solubility Factors: Particle Size • Particle size: smaller particles dissolve faster than larger particles • Stirring can increase the rate of dissolving and the solubility
Solubility Factors: Polarity • “Like Dissolves Like” Rule • Nonpolar solutes dissolve in nonpolar solvents • Polar solutes dissolve in polar solvents
Solution Video • http://www.youtube.com/watch?v=VTmfQUNLlMY
Do Now: hand in labs and if you haven’t already • Work on pages 13 to 15 of the packet
Quiz on Friday? • 10 questions • On Table F and Table G
Colligative Properties • Colligative properties are physical properties of solutions that depend on the concentration of solute in a given amount of solvent • Dependent on how much solute is present, which is based on the nature of the solute • The more particles in solution, the greater the effects
Electrolytes • Electrolytes are substances that separate to produce ions when dissolved in a solution • Conduct electricity, turn on light bulb tester • Ex: ionic compounds (salts), acids, bases • Nonelectrolytes do not produce ions (stay in one piece) in solution • Do not conduct electricity, do not turn on light bulb tester • Ex: sugars, alcohols
Electrolytes vs. Nonelectrolytes • Electrolytes • Nonelectrolytes
Electrolytes Ionic substances Acids: X-H Bases M-OH Nonelectrolytes Sugars Alcohols Electrolyte or Nonelectrolyte?
Colligative Properties • Boiling Point Elevation • the temperature at which a liquid normally boils goes up when solute particles are dissolved • Freezing Point Depression • the temperature at which a liquid normally freezes goes down when solute particles are dissolved
Boiling Point Elevation • The boiling point of a solution increases when solute particles are added • Example: • Adding salt to water raises the water’s boiling point • Water now gets hotter than 100° C (102-103°) before it boils, and pasta will cook faster
Freezing Point Depression • The freezing point of a solution decreases when solute particles are added • Example: • Putting salt on roads causes ice to melt • Ice’s freezing point becomes lower than 0°, so water stays liquid at temperatures where it would normally be solid ice
Vapor Pressure • When a substance that is normally solid or liquids at room temperature enters the gas phase, it is called a vapor • Pressure exerted by this vapor is vapor pressure • Vapor pressure ↓ with the addition of solute
Do Now and HW • Now: Complete pages 16 to 18 of the packet • HW: Complete pages 24 and 25 of the packets
Concentration • Concentration is the amount of solute dissolved in a solution • Concentrated solutions have lots of solute dissolved • Dilute solutions have only a little solute dissolved
Ways to Express Concentration • Grams solute/100mL solvent (Table G) • % composition (by mass, by volume • Parts per Million • Molarity
Percent Composition • Labels often list ingredients as a percent by mass or percent by volume
Percent Compositionby Mass and by Volume Used w/ solids Used w/ liquids Ratio of the mass (or volume) of one part compared to the mass (or volume) of the whole
Percent Composition • What is the percent by mass of sodium hydroxide if 5g of NaOH are added to 50g of water? • What is the percent by volume of alcohol is 50mL of ethanol is diluted with water to form a total volume of 3000mL?
What is the % mass of NaOH if 12.5 g is dissolved in 100 g of water?
What is the % by mass of a solution if 60 g of acetic acid are added to 90 g of water?
What is the % volume of ethanol if 45 mL are dissolved in 155 mL of water?
What is the % by volume of antifreeze if 70 mL are dissolved in 200 mL of water?
Parts Per Million (ppm) If you divide a pie into 10 equal pieces, each piece is a part-per-ten (1/10th) Divide the pie into a million pieces, and each piece is a part per million, (1/1,000,000th)
Parts Per Million (ppm) • Similar to percent composition, parts per million is a ratio between mass of the solute and the total mass of solution • Useful for very dilute solutions • In swimming pools, only 2g of chlorine for every 2 million g of water
At 40 C, carbon dioxide has a solubility of 0.0972g/100g H2O. What is the concentration of CO2, expressed in parts per million?
A substance has a solubility of 350ppm. How many grams of the substance are present in 1.0L of a saturated solution? (1 mL = 1g)
Now: Complete page 27 of the packet HW to be collected tomorrow: Review book, page 128 (some of them we’ve already done in class)
Molarity (M) Measures concentration in moles Higher molarity = more concentrated Important to note that molarity is moles of solute per liter of total solution, not solvent
Molarity (M) Example: What is the molarity of a solution that contains 4.0 moles of NaOH in 0.50 L of solution?