Chemical Equilibrium When two ____________ processes equal eachother in ________ Compare rxtion favored If ___ > ___ ________ If ___ < ___ ________ If ___ = ___ ________ EquilibriumNonequilibrium Consequences at Equilibrium [ ]’s are Rates of forward and reverse are [ ]’s are dictated by same/constant __________ establishing it quantifying it manipulating it ______________ ______________ ______________ Ch. 13 A.P. Chem opposing rate Reactions are _________reversible maybe!! stoich. and intitial [ ] Mass Action Expression [P] x /[R] y KcKc KpKp K c (RT)  n = K p K sp Q QK reverse Q K forward QK at eq. Le Chatelier’s Principle An equilibrium system that is stressed will respond to a stress in such a way to counteract the stress Conc. Changes Pressure (Volume ) Changes Temp. Changes Find Molar Solubility Spectrophotometry/ Beer’s Law

Typical problem for chapter 13. Reagents were put together at 298 K such that initially, in 95.0 mL of solution, there were in moles, the following amounts of both products and reactants in a beaker for the subsequent reaction to occur: mol mol mol A 2+ (aq) + B - (aq) ↔ AB + (aq) (colorless) (colorless) (blue)  H is negative for this process and K c = 90. Find the concentrations for all species at equilibrium and then once at equilibrium suggest four ways to get the solution to turn darker. Initial:0.24M0.42M0.55M Q= 0.55/(0.24)(0.42) Q= 5.5 Change:-x +x Eq: 0.24-x0.42-x0.55+x K= 90 = (0.55+x)/(0.24-x)(0.42-x) Q<K forward reaction favored x = 0.20 (0.04 M)(0.22 M)(0.75M) [A 2+ ]↑, [B - ]↑,Temp.↓,[AB + ]↑ 0 = 90x x + 8.5

Write the reaction equation for the dissociation of copper (II) hydroxide in water and find the K value for the reaction. Cu(OH) 2(s) Cu 2+ (aq) + 2OH - (aq) K sp = 1.6 x What if a strong acid was added to the saturated solution? OH - removed, forward rxtion favored, solid dissolved Shifts to produce more product Name 3 other ways (based on things learned this year) to get the copper (II) hydroxide to further dissolve. Add water, heat, or ammonia. What would the sol’n (above the undissolved solid) look like? Clear and colorless (conc. of Cu 2+ would be too low…no blue). Which of these would make the sol’n bluer?