1) Solute the Stuff You Are Interested In

Solutions1) Solute – the stuff you are interested in Solvent - that which dissolves the stuff Solution – the resultSolid/liquid – sugar water Liquid/liquid – alcohol in water Gas/liquid – carbon dioxide in water (soda pop)Solid/solid – gold ring Liquid/solid – jello Gas/ solid – pumice stone (??)Solid/gas – smoke Liquid gas – fog Gas/ gas – airREMEMBER – A solution is a homogeneous mixture. You can vary its composition and you can mechanically separate the components.2) Solutes can be Slightly Soluble Soluble Very soluble Insoluble – not solubleMiscible - two liquids that dissolve in each other when they are mixed (acetic acid in water) Immiscible - two liquids that do not dissolve in each other when mixed (vinegar and oil salad dressing) Emulsion – two liquids that mixed together that are usually immiscible (mayonnaise)Emulsifying agent – A substance the links the two immiscible components together forming an emulsion (egg whites used to link vinegar and oil together  mayonnaise) REMEMBER – Solubility deals with how much will dissolve.Conditions that affect solubility include: a) Temperature goes up  Solubility of Gas goes down  Solubility of Solid generally increases  Solubility of Liquid has little effect b) Pressure goes up  Solubility of Gas goes up (can of soda)  Solubility of Solid has no effect  Solubility of Liquid has no effect c) Nature of solute and solvent- “Likes” dissolve “Likes” Ionic compounds are soluble in polar solvents - (NaCl in H2O) Non-polar compounds are soluble in non-polar solvents- (Grease in gasoline)3) Rate of solution – How fast a substance will dissolve a) agitation – stirring dissolves sugar faster in water b) temperature - sugar dissolves faster in hot water c) particle size- big particles of sugar dissolve slower d) concentration - sugar dissolves slower in a solution that already contain sugar4) Concentration - How much solute is dissolved in the solution a) Percent composition b) Molarity (2.5 M HCl = 2.5 moles HCl/1 Liter solution)5) Strength – a measure of ability a) Strong acids- HCl(aq) , HNO3(aq) , H2SO4(aq)Weak acids – HC2H3O2(aq) , H2CO3(aq) , any other acid b) Strong bases- NaOH(aq) , KOH(aq) (metal hydroxides from Group IA)Weak bases – Al(OH)3(aq) , NH4OH(aq) , any other baseConcentrated Coffee not strong Coffee Dilute Tea not weak Tea 6) Solution types a) Unsaturated – solvent can still dissolve more solute b) Saturated – solvent can not dissolve any more solute c) Super saturated – Solvent has dissolved more solute than it normally holds at a given temperature (Honey)7) Electrolytes – Aqueous solutions that conduct electricity Strong electrolytes – Strong acids & bases, soluble salts Weak electrolytes – Weak acids & bases Non-electrolytes – DI water & toluene (organic compounds)8) Colligative properties are dependent on the number of particles presentLowering of the vapor pressure Lowering of freezing point Increasing the boiling point Increasing the osmotic pressure Osmosis- passage of solvent through a semi-permeable membrane Osmotic pressure-pressure required to halt the flow of solvent molecules through a semi-permeable membrane Reverse osmosis-solvent flows through the semi-permeable membrane in the reverse direction due to an increase in the osmotic pressure Living CellsIsotonic solution- solution on the out-side of a cell has same osmotic pressure as the inside the cell. No effectHypotonic solution – If cell is surrounded by a solution of lower concentration of solute particles (lower osmotic pressure), water flows into the cell (plasmolysis)Hypertonic solution – If cell is surrounded by a solution of higher concentration of solute particles (higher osmotic pressure), water flows out of the cell (crenation) Phase Diagram- H2OCritical Temperature = 647.6 K Critical Pressure = 217.7 atmLiquidVapor Solid Pressure Gas Triple Point 4.58 mm of mercury 0.0098 oCTemperature o Freezing point same as melting point = 0 C for H2O o Boiling point same as condensation point = 100 C for H2OBoiling point is the temperature where the vapor pressure of a liquid is equal to the applied pressure.Hfusion = amount of energy required to convert 1.0 gram of stuff from a solid to a liquid. Hfusion H2O = 80 calories /gram.Hvaporization = amount of energy required to convert 1.0 gram of stuff from a liquid to a gas. Hvaporization H2O = 540 calories /gram.Calorie = amount of energy required to raise the temperature of one gram of H2O one degree Celsius.BTU (British Thermal unit) = amount of energy required to raise the temperature of one pound of H2O one degree Fahrenheit. o Specific Heat (H2O/Solid) = Sp Ht (H2O/Gas) = 0.50 cal/( g x C) o Specific Heat (H2O/Liquid) = 1.0 cal/( g x C) 9) Hard water – specifically contains Ca+2, Mg+2 or Fe+3 ions - precipitates form between these ions and carbonates-1 Temporary hard water - specifically contains bicarbonate ions (HCO3 ) - boiling will remove the hardnessCa(HCO3)2(aq)  CaCO3(s) + (H2CO3 = H2O(l) + CO2(g) )10) Soap – a link between polar water and non-polar oil drops acid + base  salt + waterLard + boiled wood ashes  soap + water stearic acid + sodium hydroxide  sodium stearate + water+1 -1 C17H35COOH(s) + NaOH(aq)  Na C17H35COO (aq) + H2O(l)The Effect of Hard water on soap+1 -1 2Na C17H35COO (aq) + CaCl2(aq)  Ca(C17H35COO) 2(s) + 2NaCl(l) Lost soap Bath tub Scum 11) Water of hydration. CuSO4 5H2O copper(II) sulfate pentahydrate . CoCl2 6H2O cobalt(II) chloride hexahydrateHygroscopic – gains H2O from atmosphereDeliquescent - gains H2O from atmosphere & turns to a liquid-like solutionEfflorescent – loses H2O to atmosphereDessicant (Drying Agent)- used to keep chemicals dry in a dessicator 12) Acid-Base reactions “ Neutralization reactions” “Double Replacement Reactions”Acid + base  salt + waterHCl(aq) + NaOH(aq)  NaCl(aq) + HOH(aq)NaCl is the Salt of the Base – NaOH NaCl is the Salt of the Acid – HCl and Ba3(PO4)2 is the salt of the Base-Ba(OH)2 and the acid-H3PO4Primary Standard- 1) Usually solid 2) High molecular mass 3) Stable at 100oC 4) High purityIndicator- Phenolphthalein Acid/colorless Neutral/colorless Base/pinkIndicators tell when the titration is over13) Buffers – resist changes in pH (see pH/pOH calculations) a) Sodium bicarbonate neutralizes an acidNaHCO3 + HCl  NaCl + H2CO3 ( H2CO3  H2O + CO2) b) Sodium bicarbonate neutralizes a baseNaHCO3 + NaOH  Na2CO3 + H2OIn both cases the sodium bicarbonate either removes H+1 or OH-1 from the solution. This is how a buffer works. Blood is a very complex buffer system with a pH of about 7.4 The primary buffer is a mix of -1 H2CO3 (H2O(l) and CO2(g) ) and HCO3 . Stoichiometry a) Mass-Mass Problems1) Balance the reaction 2) Calculate the molecular mass of the known and the unknown 3) Calculate the number of moles of known 4) Calculate the number of moles of unknown 5) Calculate the number of grams of unknownGrams known  moles known  moles unknown  grams unknownMM of Known Balanced MM of unknown ReactionExampleCalculate the mass of nitrogen needed to make 34 grams of ammonia.1) Balance the reaction:N2 + 3H2  2NH32) Calculate the molecular mass of the known and the unknown: known [email protected] = 14.0 unknown 2N @ 14 = 28 g N23H @ 1.0 = 3.0 1 mole N217 g NH3 mole NH3 3) Calculate the number of moles of known:(34 grams NH3)(1mole NH3/17 grams NH3) = 2 moles NH34) Calculate the number of moles of unknown:(2 moles NH3) ( 1 mole N2 / 2 moles NH3) = 1 mole N25) Calculate the number of grams of unknown:(1 mole N2)(28 grams N2/mole N2) = 28 grams N2All Together grams N2 = (34 grams NH3) (1mole NH3) ( 1 mole N2) (28 grams N2) = 28 grams N2(17 grams NH3) (2 moles NH3) (1 mole N2) b) Molarity = moles solute/ Liter solution2.0 moles NaOH/ 1 Liter solution = 2.0 molar NaOH = 2.0 M NaOHCalculate molarity (moles/Liter) Convert: Liters  moles  grams Grams  moles  Liters c) DilutionConc1 x Vol1 = Conc2 X Vol2 d) Percent composition = (grams solute/grams solution) x 100Convert grams solute  grams solution grams solute   grams solvent grams solvent   grams solution e) pH / pOH / [H+1] / [OH-1]1) acid pH =-Log [H+1] [H+1] is the concentration of hydrogen ions in moles/Liter2) base pOH =-Log [OH-1] [OH-1] is the concentration of hydroxide ions in moles/LiterCalculator work Type 1: [H+1] / Log / (+/-) gives pH Type 2: (+/-) / Log / [H+1] / enter gives pH[H+1] can be replaced with [OH-1] for bases3) Acid [H+1] = 10-pH4) Base [OH-1] = 10-pOHCalculator work Type 1: pH / (+/-) / inverse Log gives [H+1] Type 2: inverse Log / (+/-) / pH / enter gives [H+1] pH can be replaced with pOH for bases5) acid/base pH + pOH = 14 More Acidic Neutral More Basic pH 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 pOH 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0Strong Acid Weak Acid Weak Base Strong Base HCl HC2H3O2 NH4OH NaOH Stomach Acid Vinegar Ammonia Water Oven CleanerDe-ionized water

1) Solute the Stuff You Are Interested In

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