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18) Which two equations illustrate water (H2O) acting as a proton donor? CH3COO – (aq) + H2O(l) → OH–(aq) + CH3COOH(aq) HNO3 (aq) + H2O(l)    → H3O+(aq) + NO3 – (aq)   2Na(s) + 2H2O(l)   → 2NaOH(aq)  + H2(g)     NH3 (g) + H2O(l)  → NH4OH(aq)

29) Consider the following reaction:                 N2(g) + O2(g)     2NO(g)Suppose we have a reaction mixture in which the initial concentration of [N2] is 0.20 M and the initial concentration of [O2] is 0.20 M. The Kc = 0.10. Find the equilibrium concentrations of N2, O2 and NO. To solve this problem, please use the I.C.E. table.

8) Consider the gas-phase equilibrium system represented by the equation:                                                                                               2H2O (g) + Heat      2H2(g) + O2(g)           [Hint = The reaction is Endothermic] Given that the forward reaction is endothermic, which of the following changes will decrease the equilibrium amount of H2O(g)?

22) Which of the following combinations cannot produce a buffer solution? HNO2 and NaNO2 HCN and NaCN HClO4 and NaClO4 NH3 and (NH4)2SO4

33) A solution made by dissolving 9.81 g of a nonvolatile nonelectrolyte in 90.0 g of water boiled at 100.37 o C at 760 mm Hg. What is the approximate molecular weight of the substance? (For water, Kb = 0.51 o C/m)    [DTb = Kb * m]                                                       

13) Consider the following reaction mechanism: Step1:  I–Cl  +   H2     →    H–I  +  HCl  (Slow)                                     Step 2:  I–Cl  +   H–I   →  HCl  +  I2     (Fast) The species HCl _________ while H–I _________________.

28) Complete the statement to give a correct answer. The stronger the acid, __________

16) If the rate law for the overall reaction [2A + 3B → Products] is first order in A and second order in B, then the rate law for this reaction is____

21) Consider the following equilibrium:                                           Which of the following changes will cause the equilibrium to shift to the left?                 2SO3(g)  Arrow(1).png 2SO2(g) + O2(g)    à  [DHº = +198 kJ]

25) What is the coefficient of the permanganate ion (MnO4-1) on the reactant side when the following equation is balanced? How many electrons are being transferred when Mn in permangnate ion (MnO4-1 ) is being reduced to Mn+2?                        MnO4-1 + Br-1 → Mn+2 + Br2   (acidic solution)