Review 1 For test 1 Chapter 12 and 13 Test will have part 1 Multiple choice and part 2 show work problems One can receive partial credit in Multiple choice if work is shown or concept is explained BRING A SCANTRON

Concentration Units Mole Fraction (X) M = moles of solute liters of solution m = mass of solvent (kg) Molarity (M) Molality (m) Weight (mass) % x 100% mass of solute mass of solute + mass of solvent Xi = moles solute (i) Total moles in solution Mole Fraction (X) Mole % of A = mole fraction A*100 Percent by volume: milliliters of solute/milliliters of solution (then multiplied by 100%) Mass/volume percent: grams of solute/milliliters of solution (then multiplied by 100%) % by mass =

Henry’s law for Gas solubility Sg (mol/L) Sg =KHPg ROULT’s Law Psolution = Xsolvent  Posolvent Psolution = the vapor pressure of a mixture of solute and solvent Po = the vapor pressure of the pure solvent Xsolvent = the mole fraction of the solvent. If 2 liquids A and B are mixed then Vapor of each of them in the mixture are PA = XA P0A PB = XB P0B Ptotal = PA ++ PB

Colligative Properties of Nonelectrolyte Solutions Colligative properties are properties that depend only on the number of solute particles in solution and not on the nature of the solute particles. Vapor-Pressure Lowering P1 = X1 P 1 Boiling-Point Elevation DTb = Kb m Freezing-Point Depression DTf = Kf m Osmotic Pressure (p) p = MRT Electrolyte/IONIC Substance Solutions (i is Vant Hoff factor) Boiling-Point Elevation DTb = i Kb m Freezing-Point Depression DTf = i Kf m Osmotic Pressure (p) p = iMRT 4

In general for the reaction: Chapter 12 Kinetics Average Rate In general for the reaction: aA + bB  cC + dD (M/s) Initial Rate x and y are the reactant orders determined from experiment. x and y are NOT the stoichiometric coefficients.

Insert Table 13.2

Both A and Ea are specific to a given reaction. The Arrhenius Equation k is the rate constant T is the temperature in K R is the ideal-gas constant (8.314 J/Kmol) Ea is the activation energy A is known the frequency or pre–exponential factor Both A and Ea are specific to a given reaction.

Uncatalyzed reaction Catalyzed reaction Catalysts Lowers activation energy Changes Reaction mechanism But does not change Enthalpy Speeds up reaction Reaction Mechanisms, Overall Reaction, Molecularity (unimolecular, bi molecular etc for each Step in a multistep reaction pathway) Intermediates Rate Detreminating step is the slowest step and makes up the overall reaction rate law. Difference between a CATALYST vs Intermediate