Rubric for Exam 3 Spring 2014 Chapter 16 1 Understand how an equilibrium is established and what it means the important points raised in the notes and in class 2 Be able to write equilibrium constant expressions for both homogeneous and heterogeneous equilibria and for gas phase reactions 3 Understand how rates rate laws and equilibria relate to the reaction stoichiometry 4 Be able to tell if a reaction is reactant favored or product favored 5 Understand the difference between Q and K and how Q is used 6 Be able to perform equilibrium calculations to a find K given equilibrium concentrations b find an equilibrium concentration given K and other concentrations c find equilibrium concentrations given K and initial concentrations simple systems A B more complex systems use of square roots when do you need to use the quadratic equation when you can assume that x small 7 Be able to manipulate equilibrium expressions to get values for related expressions e g direction or coefficients 8 Be able to manipulate equilibrium expressions to get values for new reactions adding equilibria 9 Understand and apply Le Chatelier s Principle with regard to concentration changes volume changes for gases temperature changes endothermic or exothermic reactions Be able to predict the direction in which the equilibrium will shift See extra problems posted on Bb Chapter 17 1 Know the strong acids and bases OWL CHM 2045 2 Understand and apply the Bronsted Lowry model of acids and bases a definitions including monoprotic etc amphiprotic examples b conjugate acid base pairs 3 Understand the acid base properties of water Apply Kw to determine the concentrations of the hydronium or hydroxide ion H3O or OH 4 Understand and apply pH concepts Be able to a determine pH given H3O b determine H3O given pH 5 Do H3O OH pH and pOH interconversions eqns 17 1 17 4 6 Apply acid base equilibria concepts Ka Kb and relation between them 7 Understand meaning in Ka Kb table Table 17 3 Understand the relation between Ka and acid strength as well as that of the conjugate base of the acid Note you do not have to memorize values in the table 8 Understand that salts are not always neutral and be able to tell if a solution of a salt will be neutral acidic or basic 9 Understand the relation between Ka and pKa as well as Kb and pKb and apply this to acid base strengths Be able to calculate Kb for a conjugate base from Ka for the acid and vice versa using equation 17 8 10 Be able to predict the direction of an acid base reaction to which side does it lie based on comparisons of the acid base pairs Ka and Kb values will be given 11 Be able to perform equilibrium calculation for weak acids and bases a finding Ka from pH and HA o b using Ka to find H3O or pH c ditto for bases and solutions of salts such as NaF or NH4Cl 12 Understand the similarities and differences between monoprotic and polyprotic acids and the fact that the pH depends on the H3O generated in the first ionization step 13 Understand the Lewis model of acids and bases Be able to determine if a reaction is an acid base process in the Lewis vs the Bronsted sense