Agenda: Warm-up: Explain the solvation process Homework: New Element Project Agenda: Warm-up: Explain the solvation process Review – terms, importance, “likes dissolve likes” Solubility Curves What can they tell us about solutions? Measuring concentration of solutions

Warm-up: Solvation Process Explain what is happening when an ionic compound is dissolved in water (called solvation or hydration) View the video - what are key steps that need? How does the water molecules interact with the ionic compound? http://group.chem.iastate.edu/Greenbowe/sections/projectfolder/flashfiles/thermochem/solutionSalt.html

a. Making Solutions: Molecules (Covalent compounds) General Rule: “Likes dissolve likes” Polar solutes can dissolve in polar solvents. Examples:

Organic solvents Non-polar solute can dissolve in non-polar solvents Examples: To remove oily stains in dry-cleaning Lipids will dissolve in hydrocarbon To clean oil based paints To manufacture plastics, man-made fibers, adhesives

Solution process

Solution process Animations https://www.youtube.com/watch?v=EBfGcTAJF4o

b. Making Solutions: Factors that impact the solubility of solids in liquids Energy is involved – 2 steps Endothermic to separate solute & solvent particles Exothermics – attraction between solvent & solute particles Factors affecting solids dissolving in liquids General trend to increase solubility Chemical components of solute and solvent Intermolecular forces High attraction between solute and solvent particles Temperature Particle size Agitation (amount of stirring)

c. Measuring Concentration Solubility: number of grams of solute in 100 grams of water at 20℃ Solubility Curves Saturated solutions Unsaturated Supersaturated http://www.youtube.com/watch?v=XSGvy2FPfCw http://www.youtube.com/watch?v=1y3bKIOkcmk&feature=related

Interpreting solubility curves Y axis X axis Lines If the amount needed is more or less than 100 g of H₂O 1 g H₂0 = 1 mL H₂0

c. Making solutions: Factors that affect the solubility of gases in liquids Think about soda (carbonated drinks) Factors affecting gases General trends to increase solubility Temperature Pressure

Solubility Rules determined under specified concentration (often 0 Solubility Rules determined under specified concentration (often 0.1% molarity) Category Ions Except with these ions Examples Soluble cations Group 1 ions and ammonium, NH4+ No exceptions Na2CO3, LiOH, and (NH4)2S are soluble. Soluble anions NO3- and C2H3O2- Bi(NO3)3, and Co(C2H3O2)2 are soluble. Usually soluble anions Cl-, Br-, and I-   Soluble: Exceptions: Ag+ and Pb2+ CuCl2 is water soluble, but AgCl is insoluble. SO42- Soluble Exceptions: Ba2+ and Pb2+ FeSO4 is water soluble, but BaSO4 is insoluble. Usually insoluble anions CO32-, PO43-, and OH- Insoluble: Exceptions: group 1 elements and NH4+ CaCO3, Ca3(PO4)2, and Mn(OH)2 are insoluble in water, but (NH4)2CO3, Li3PO4, and CsOH are soluble.

d. Measuring Concentrations Molarity (M) by definition = Molarity = Moles of solute 1 Liter of solution Therefore: 2 molar solution = __________________ Discovery Education video Standard Deviants School Chemistry: solutions & dilutions

Molarity: moles of solute liters of solution

Molarity problems M= moles_______ 1 Liter solution What I s the molarity of a solution in which 58 gram of NaCl are dissolved in 1.0 L of solution? What is the molarity of a solution in which 10.0 grams of silver I nitrate is dissolved in 500 mL of solution? How many grams of potassium nitrate should be used to prepare a 2.0 L of a 0.5 molar solution?

Steps needed in molarity calculations Moles For grams: Liters of solution If less than 1L ? mL = 1L Comparison __________ = moles of solute 1 liter of solution

Molarity practice To what volume should 5.0 g of KCl be diluted in order to prepare a 0.25M solution? How many grams of copper II sulfate – penta hydrate are needed to prepare 100 mL of a 0.10M solution?

9g. Dilution of concentrated solutions: V₁M₁= V₂M₂ Molarity by dilution practice problems Most reagents are sold & sorted in concentrated solutions How much concentrated 18M sulfuric acid is needed to prepare 250mL of a 6.0M solution? How much concentrated 12M hydrochloric acid is needed to prepare 100 mL of a 2.0 M solution?

To what volume should 25 mL of 15 M nitric actid be diluted to prepare a 3.0 M solution? To how much water should 50 mL of 12 M hydrochloric acid be added to produce a 4.0 M solution? To how much water should 100 mL of 18M sulfuric acid be added to prepare 1.5 M solution?

Colligative Properties The properties of the solution that depend on the number of particles in solution, not the identity of the solute. The solvent properties will be changed. NaCl CaCl₂ AlCl₃ Melting point depression; boiling point elevation; Vapor pressure lowering

Resources http://www.karentimberlake.com/solution.htm http://www.afn.org/~afn02809/powerpoint-list.htm http://www.chemistrygeek.com/chemistrypowerpoint/Student%20Ch%2015%20Solutions.ppt http://college.cengage.com/chemistry/general/zumdahl/world_of_chem/1e/instructors/ppt/figures/viewindex.html

Solution process