1. Complete an Initial/Change/Final molarity table for each. (a) A + 2B C (b) 3D + E 2F I I

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1 HOMEWORK 1A Definitions Molarity; hemical Equilibrium; Equilibrium onstant Questions 1. omplete an Initial/hange/Final molarity table for each. (a) A + 2B (b) 3D + E 2F I I F F 2. Write the correct equilibriumconstant expressions for the following reactions. (a) 4NH 3 (g) + 7O 2 (g) 4NO 2 (g) + 6H 2 O (g) (b) 2NO 2 (g) + 7H 2 (g) 2NH 3 (g) + 4H 2 O (g) (c) NH 4 l (s) NH 3 (g) + Hl (g) (d) 2ZnS (s) + 3O 2 (g) 2ZnO (s) + 2SO 2 (g) (e) l 2 (g) + H 2 O (g) 2Hl (g) + ½O 2 (g) 3. In a 2.50 L flask at 298 K, mol SO 2, mol O 2, and mol SO 3 are at equilibrium. alculate the equilibrium constant for the reaction: 2SO 2 (g) + O 2 (g) 2SO 3 (g) 4. The equilibrium constant for the reaction: NO (g) + ½O 2 (g) NO 2 (g) at 450 K is 1.25 x 10 2 (a) At equilibrium are the products or reactants favored for this reaction? (b) What is the numerical value of K eq for the reaction: 2NO (g) + O 2 (g) 2NO 2 (g) (c) What is the numerical value of K eq for the reaction: 2NO 2 (g) 2NO (g) + O 2 (g) 5. The equilibrium constant for the reaction: N 2 (g) + O 2 (g) 2NO (g) at 2,130º is 2.0 x For the following conditions, determine whether the reaction is spontaneous forward or in reverse, or whether it is at equilibrium. (a) A 1.0 L box contains 0.02 mole of N 2, 0.01 mole of O 2, and 0.02 mole of NO at 2,130º. (b) A 1.0 L box contains 0.2 mole of N 2, 0.01 mole of O 2, and 0.02 mole of NO at 2,130º. (c) A 1.0 L box contains 0.2 mole of N 2, 0.01 mole of O 2, and 0.2 mole of NO at 2,130º.

2 HOMEWORK 1B Definitions K c ; K p ; Percent Dissociation Questions 1. At 1,476 K the equilibrium constant for the reaction: O (g) + ½O 2 (g) O 2 (g) is given by: K c = 2.50 x 10 5 (a) Determine the numerical value of K p for the above reaction. (b) What would be the numerical value of the K p for the reaction: 2O (g) + O 2 (g) 2O 2 (g) 2. When sulfur trioxide is produced from the combustion of sulfur dioxide at 1,000. K, a sample of the equilibrium gas mixture showed atm of SO 2, atm of O 2, and atm of SO 3. (a) alculate the equilibrium constant, K p, for the reaction: 2SO 3 (g) 2SO 2 (g) + O 2 (g) (b) Determine the numerical value of K c for the above reaction. (c) alculate the numerical value of the K c for the reaction: SO 2 (g) + ½O 2 (g) SO 3 (g) 3. omplete an Initial/hange/Equilibrimu molarity table for each. (a) A + 2B (b) 3D + E 2F I I E E 4. At 298 K, K c = 2.25 x 10 2 for the reaction: 2NO (g) N 2 (g) + O 2 (g) (a) If a container is initially charged with 7.50 M NO, calculate the equilibrium concentration of NO. (b) What is the percent dissociation of NO? 5. A solution is prepared by dissolving moles of calcium chloride in enough water to make ml of solution. (a) alculate the molarity of the calcium chloride in the solution. (b) A ml sample of the calcium chloride solution is mixed with 10.0 ml of water. alculate the molarity of the calcium chloride in the new solution. (c) alculate the molarities of the calcium ions and the chloride ions in the new solution.

3 HOMEWORK 1 Questions 1. K p is at 350º for the reaction: 2NO (g) N 2 (g) + O 2 (g) The tank is initially charged with atm NO, atm N 2, and atm O 2 at 350º. (a) Is the forward or reverse reaction spontaneous? (b) alculate the pressure of NO once equilibrium has been established. 2. For the reaction: 2lF (g) l 2 (g) + F 2 (g) A 2.50 L flask at equilibrium contains moles of lf, moles of l 2, and moles of F 2. (a) alculate the numerical value of the K c for the above reaction. (b) If moles of F 2 is added to the flask at equilibrium, calculate the new concentration of lf when equilibrium is reestablished. 3. Nitrogen reacts with oxygen to produce nitrogen monoxide by the following reaction: N 2 (g) + O 2 (g) 2NO (g) The K c for this reaction at 150º is A flask at 150º is initially charged with enough nitrogen to make its concetration M. alculate the concentration of oxygen gas at 150º that must initially be in the flask to make the equilibrium concentration of nitrogen monoxide M. 4. omplete each of the following IE tables, and tell if the x in the IE table will be large or small. (a) K eq = 1 x 10 9 (b) K eq = 1 x 10 9 A + 2B A + 2B I I E E (c) K eq = 1 x 10 9 (d) K eq = 1 x D + E 2F 2D + E 2F I I E E

4 5. The equilibrium constant for the reaction: 2Hl (g) H 2 (g) + l 2 (g) at 25º is 6.2 x (a) Why was it unnecessary to be told whether the value is for K p or K c? (b) Without any calculations, what does the numerical value of this constant tell you about the decomopition of Hl? (c) If mole of Hl is placed in a 1.0 liter tank and allowed to come to equilibrium at 25º, will the x in the IE table be large or small? What will be the final concentration of the hydrogen gas, in moles per liter? (d) If mole of l 2 and mole of H 2 are placed together in a 1.0 liter tank and allowed to come to equilibrium at 25º, will the x in the IE table be large or small? What will be the final concentration of the hydrogen gas, in moles per liter? HOMEWORK 1D Definitions Total Pressure; Lehatelier s Principle; Endothermic; Exothermic; hange in Enthalpy Questions moles of NO, 5.00 moles of lno, and 2.00 moles of l 2 are placed in a 25.0 liter tank at a temperature of 503 K. After the reaction has come to equilibrium, there are 6.12 moles of lno in the tank. (a) Write a balanced equation for the reaction producing 1 mole of lno from the other two substances. (b) alculate K c for this reaction at 503 K, with proper units. (c) alculate K p for this reaction at 503 K, with proper units. 2. Ammonia decomposes according to the reaction: 2NH 3 (g) N 2 (g) + 3H 2 (g) A 2.00 liter tank is originally charged with moles of ammonia, and at equilibrium it is found that the ammonia is 16.5% decomposed. alculate the numerical value of the K c for the above reaction. 3. A tank of O 2 has an initial pressure of 2.00 atm. The O 2 undergoes the reaction: 3O 2 (g) 2O 3 (g) and at equilibrium the total pressure is 1.75 atm. Find K p for the reaction

5 4. At 350 K, a 14.0 g sample of N 2 O gas is placed in an evacuated 10.0 liter container. (a) What is the pressure of N 2 O in the container, measured in atmospheres? (b) The N 2 O gas decomposes, as shown by the following equation: 2N 2 O (g) 2N 2 (g) + O 2 (g) If the N 2 O from (a) is 20.0% decomposed when equilibrium is established at 350 K, calculate the value of the K p for this decomposition reaction. (c) If the temperature of the container above is raised to 450 K, the K c for this decomposition reaction is 2.7 x 10 2 M. How many moles of O 2 must be added to the container to reduce the quantity of N 2 O to moles at equilibrium. 5. The following reaction is exothermic: Pl 3 (g) + l 2 (g) Pl 5 (g) For each of the following disturbances, indicate (1) the direction the equilibrium will shift, and (2) whether the new equilibrium pressure of Pl 5 will be higher, lower, or remain the same. (a) The addition of a catalyst (b) A decrease in the volume of the reaction container (c) Addition of chlorine gas at constant volume (d) An increase in temperature (e) Adding argon gas to the reaction container (f) Addition of Pl 5 gas at constant volume. 6. The following reaction is endothermic: ao 3 (s) ao (s) + O 2 (g) For each of the following disturbances, indicate (1) the direction the equilibrium will shift, (2) whether the new equilibrium moles of O 2 will be higher, lower, or remain the same, and (3) whether the new equilibrium pressure of O 2 will be higher, lower, or remain the same. (a) An increase in temperature (b) A decrease in the volume of the reaction container (c) Addition of carbon dioxide gas at constant volume (d) Addition of solid ao 3 at constant volume. 7. For the same reaction in problem 6, indicate whether the new equilibrium mass of ao 3 will be higher, lower, or remain the same. (a) Addition of carbon dioxide gas at constant volume (b) An decrease in the volume of the reaction container 8. The following reaction is exothermic: N 2 (g) + 3H 2 (g) 2NH 3 (g) For each of the following properties, indicate how it must change to force the equilibrium to shift to the right. (a) Pressure (b) Temperature (c) oncentration of N 2 (d) oncentration of NH 3

6 HOMEWORK 1E Definitions Arrhenius Acid; Arrhenius Base; Strong Acid; Weak Acid; Strong Base; Weak Base; Amphoteric; Brønsted Acid; Brønsted Base; IonProduct onstant for Water; ph; poh Questions 1. Rank the following from weakest acid to strongest acid: HlO 4, HlO 3, HlO 2 2. Rank the following from strongest base to weakest base: NaOH, Fe(OH) 2, Fe(OH) 3 3. Identify the acid, base, conjugate acid and conjugate base for the following reaction: 3 H 7 NH 2 + H 3 OH 3 H 7 NH H 3 O 4. Identify the conjugate base for each of the following: (a) HF (b) H 2 O (c) NH 3 (d) HSO 4 5. Identify the conjugate acid for each of the following: (a) F (b) H 2 O (c) NH 3 (d) HSO 4 6. For each acid, (1) tell whether it is a strong, weak, or non acid, (2) give its conjugate base, and (3) tell whether the conjugate base is strong, weak, or non base (a) HIO 3 (b) HN (c) HNO 2 (d) H 3 PO 4 7. For each base, (1) tell whether it is a strong, weak, or non base, (2) give its conjugate acid, and (3) tell whether the conjugate acid is strong, weak, or non acid (a) NH 3 (b) NaOH 8. Give the missing information for each solution at 25º: (a) Solution x 10 3 (b) Solution x 10 5 [H 3 O + ] [OH ] ph poh (c) Solution (d) Solution A detergent box must bear a warning label if its contents will form a solution of ph greater than 11, because a strong base degrades protein structure. Should a box bear such a label if the H 3 O + concentration of a solution of its contents is 2.5 x moles per liter? 10. A solution of ammonia has a hydronium ion concentration of 8.0 x 10 9 moles per liter. What is the poh of the solution? 11. The K w for pure water at 60º is 9.5 x (a) alculate the ph of pure water at 60º. (b) Is pure water at 60º acidic, basic, or neutral?

7 HOMEWORK 1F Definitions Acid Ionization onstant; Base Dissociation onstant Questions 1. For the following acids, write (1) the reaction for their ionization in water, and (2) their acid ionization constant expression. (a) HlO 2 (b) HN (c) HO 2 H 2. From data on Handout 3, rank these acids from weakest to strongest: HO 6 H 5, HlO 2, H 2 O, NH For the following bases, write (1) the reaction for their ionization in water, and (2) their base dissociation constant expression. (a) H 3 NH 2 (b) F (c) NO 2 4. For the following acids: HBrO 3, HBrO 2, HBrO (a) rank them from weakest to strongest (b) predict the numerical values for their acid ionizations constants 5. alcualte the ph of each of the following strong acid and strong base solutions. (a) M Hl (b) 0.02 M HNO 3 (c) M NaOH (d) M Ba(OH) 2 6. The acid ionization constant for arsenious acid, HAsO 2, is 6.0 x (a) alculate the ph of a 0.10 M solution of arsenious acid. (b) alculate the poh of a 0.10 M solution of arsenious acid. 7. A 0.10 M solution of trichloroacetic acid, l 3 O 2 H, is 1.3% ionized. (a) alculate the K a for the acid. (b) alculate the ph of the solution. 8. A 0.25 M solution of iodous acid has a ph of (a) alculate the K a for the acid. (b) alculate the percent ionization of HNO The base dissociation constant for the organic base pyridine, 5 H 5 N, is 1.58 x (a) alculate the ph of a 0.10 M pyridine solution. (b) alculate the concentration of 5 H 5 NH + in the 0.10 M pyridine solution. 10. The base dissociation constant for the weak base hydrazine, N 2 H 4, is 2.0 x alcualte the molar concentration of hydrazine would yield a poh of 3.52.

8 HOMEWORK 1G Definitions Polyprotic Acid; Hydrolysis Questions 1. Rank the following acids from weakest to strongest: H 3 BO 3, H 2 BO 2 3, HBO 3 2. A solution is M in sulfurous acid. (a) alcualte the concentrations of H +, HSO 3, SO 2 3, and H 2 SO 3 in the sulfurous acid solution. (b) alcualte the ph of the solution? 3. A solution is 0.30 M in sulfuric acid. (a) alculate the concentrations of H +, HSO 4, SO 2 4, and H 2 SO 4 in the sulfuric acid solution. (b) alcualte the ph of the solution? 4. A solution is 0.18 M in ammonium chloride. (a) Which ion is reacting with water? (c) What constant is used to calculate the ph? 5. A solution is M in sodium acetate. (a) Which ion is reacting with water? (c) What constant is used to calculate the ph? (b) Is the solution acidic or basic? (d) alculate the ph of the solution. (b) Is the solution acidic or basic? (d) alculate the ph of the solution. 6. A M solution of sodium iodite, NaIO 2, has a ph of (a) Write the equation for the hydrolysis of NaIO 2. (b) Write the equilibrium constant expression for the hydrolysis reaction. Is it a K a or K b expression? (c) alculate the value for the equilibrium constant in (b). (d) alculate the acid ionization constant for HIO 2.

9 HOMEWORK 1R 1. Write the K c and K p expressions for the following reactions, andindicate their proper units. (a) 2O 2 (g) 2O (g) + O 2 (g) (b) Pl 3 (g) + 3NH 3 (g) 3Hl (g) + P(NH 2 ) 3 (g) (c) H 2 O (g) + (s) O (g) + H 2 (g) 2. At 298 K the equilibrium constant for the reaction: N 2 O 4 (g) 2NO 2 (g) is given by: K c = 4.63 x 10 3 (a) What is the numerical value of K c for the reaction: 2NO 2 (g) N 2 O 4 (g) (b) What is the numerical value of K c for the reaction: ½N 2 O 4 (g) NO 2 (g) 3. The equilibrium constants for the following reactions are given: H 2 O 3 (aq) HO 3 (aq) + H + (aq) K c = 4.2 x 10 7 HO 3 (aq) O 3 2 (aq) + H + (aq) K c = 4.8 x alculate the equilibrium constant for the reaction: H 2 O 3 (aq) O 3 2 (aq) + 2H + (aq) 4. The equilibrium constant for the reaction: H 2 (g) + I 2 (g) 2HI (g) At 430º is 1.6 x The reaction absorbs heat. Determine whether the reaction is spontaneous forward or in reverse, or whether it is at equilibrium. (a) A 1.0 L box contains mole of H 2, mole of I 2, and 0.40 mole of HI at 430º. (a) A 1.0 L box contains 0.10 mole of H 2, 0.10 mole of I 2, and 0.40 mole of HI at 430º. (a) A 1.0 L box contains mole of H 2, 0.10 mole of I 2, and 0.40 mole of HI at 430º. 5. At 350.º, the equilibrium constant for the reaction: 2SO 3 (g) 2SO 2 (g) + O 2 (g) is given by: K p = 1.8 x 10 5 (a) What are the proper units (in atmospheres) for the given K p value? (b) What is the numerical value of K c for the reaction? (c) What would be the proper units for the K c?

10 6. Nitrogen monoxide reacts with nitrogen dioxide to produce dinitrogen trioxide by the following reaction: NO (g) + NO 2 (g) N 2 O 3 (g) (a) A 250. ml flask is initially charged with 9.35 grams of dinitrogen trioxide. alculate the concentration of the dinitrogen trioxide, in moles per liter, before any reaction occurs. (b) When the container is heated to 190º and equilibrium reached, the dinitrogen trioxide was found to be 36.4% dissociated. alculate the K c for the reaction at 190º, and give its proper units. (c) A different 250. ml flask is initally charged with 6.25 grams of nitrogen dioxide. How many grams of nitrogen trioxide must be added to the flask so that at 190º the equilibrium concentration of dinitrogen trioxide will be moles per liter. 7. Ammonium carbamate, NH 4 O 2 NH 2, decomposes as follows: NH 4 O 2 NH 2 (s) 2NH 3 (g) + O 2 (g) Starting with only the solid, it is found that at 40 the total gas pressure at equilibrium is atm. alculate the numerical value of K p with proper units. 8. Phosgene gas, Ol 2, can be prepared from carbon monoxide gas and chlorine gas as follows: O (g) + l 2 (g) Ol 2 (g) 3.00 x 10 2 moles of pure phosgene gas was placed in a 1.50 L container, heated to 800. K, and at equilibrium the pressure of O was found to be atm. alculate the numerical value of K p with proper units. 9. The equilibrium constant for the reaction: 2HF (g) H 2 (g) + F 2 (g) at a particular temperature is 3.6 x A L container is originally charged with moles of H 2 and moles of F 2, and allowed to reach equilibrium. alculate the equilibrium concentrations, in moles per liter, of H 2 and F 2 in the container. 10. Nitrosyl chloride, NOl, decomposes as follows: 2NOl (g) 2NO (g) + l 2 (g) When a 2.50 mole sample of NOl was placed in a 1.50 L chamber at 400., and allowed to reach equilibrium, it was found to be 28.0% decomposed. alculate the K p and K c for the reaction, with proper units for each. 11. At 500 K, the equilibrium constant for the reaction: SF 6 (g) SF 4 (g) + F 2 (g) is given by: K p = 2.50 x 10 1 A flask is originally charged with atm of SF 6 and an unknown amount of F 2. At equilibrium the pressure of SF 6 was found to be atm. Find the initial pressure of the F 2.

11 12. The following reaction produces the deep blue tetraamminecopper(ii) complex ion: u 2+ (aq) + 4NH 3 (aq) u(nh 3 ) 4 2+ (aq) To determine the equilibrium constant for the reaction above, an equilibrium solution was prepared by mixing together ml of a M u(no 3 ) 2 solution with 5.00 ml of a M NH 3 solution. The absorbance of the equilibrium solution was measured at a wavelength of 546 nm in a 1.00 cm cuvet, and found to be (a) Determine the initial concentrations of u 2+ and NH 3 in the equilibrium solution. (b) Using the calibration line to the right, determine the equilibrium concentration of u(nh 3 ) 4 2+ in the equilibrium solution. (c) Determine the equilibrium concentrations of u 2+ and NH 3 in the equilibrium solution (d) Determine the equilibrium constant for the given reaction. 13. The following reaction is exothermic: SO 2 (g) + l 2 (g) SO 2 l 2 (g) For each of the following disturbances, indicate (1) the direction the equilibrium will shift, and (2) whether the new equilibrium moles of SO 2 l 2 will be higher, lower, or remain the same. (a) The addition of a catalyst (b) A decrease in the volume of the reaction container (c) Addition of SO 2 gas at constant volume (d) The removal of SO 2 l 2 gas at constant volume (e) An increase in temperature (f) Adding helium gas to the reaction container 14. The following reaction is endothermic: 2Fe(OH) 3 (s) 2Fe 2 O 3 (s) + 3H 2 O (g) For each of the following disturbances, indicate (1) the direction the equilibrium will shift, and (2) whether the new equilibrium pressure of water vapor will be higher, lower, or remain the same. (a) The addition of a catalyst (b) A decrease in the volume of the reaction container (c) Addition of water vapor at constant volume (d) An increase in temperature (e) Adding argon gas to the reaction container (f) Addition of solid Fe(OH) 3 at constant volume.

12 15. For the following equilibrium reaction: Ag 2 O 3 (s) 2Ag + (aq) + O 3 2 (aq) write the net ionic equation for each of the following shifts, and underline the added substance that caused the shift. (a) The addition of AgNO 3 (aq) (b) The addition of Nal (aq) (c) The addition of Hl (aq) 16. For the following acids, write (1) the reaction for their ionization in water, and (2) their acid ionization constant expression. (a) HlO 2 (b) NH Rank the following acids from weakest to strongest: H 2 SO 4, H 2 SO 3, HSO 3, H 2 S, HS 18. Rank the following acids from weakest to strongest: H 3 H 5 O 2, HNO 2, HBr, H 2 O, 5 H 5 NH For the following bases, write (1) the reaction for their ionization in water, and (2) their base dissociation constant expression. (a) (H 3 ) 3 N (b) 6 H 5 O 20. Rank the following bases from weakest to strongest: NH 3, H 2 NNH 2, H 3 NH Rank the following bases from weakest to strongest: F, H 2 O, HO 2 3, O What is the ph of each of the following strong acid or strong base solutions? (a) M HlO 4 (b) M a(oh) Formic acid, HO 2 H, is a weak acid. (a) Write the equation for the ionization of formic acid. (b) Write the equilibrium constant expression for the reaction. (c) If a 0.10 M formic acid solution has a ph of 2.39, what is formic acid s acid ionization constant? (d) If a 0.25 M formic acid solution is 2.7% ionized, what is the ph of the solution? 24. The acid ionization constant for benzoic acid, 6 H 5 O 2 H, is 6.5 x (a) Write the equation for the ionization of benzoic acid. (b) Write the equilibrium constant expression for the reaction. (c) What is the ph of a 0.10 M solution of benzoic acid? (d) What is percent ionization of benzoic acid in a 0.10 M solution? 25. Propylamine is a weak base that reacts with water as follows: 3 H 7 NH 2 + H 2 O 3 H 7 NH OH The base dissociation constant for this reaction, K b, is 4.8 x (a) What is the concentration of 3 H 7 NH + 3 in a solution that was originally M in propylamine? (b) What is ph of the solution?

13 26. A solution is M in ascorbic acid. (a) What are the concentrations of H 3 O +, H 6 H 6 O 6, 6 H 6 O 6 2, and H 2 6 H 6 O 6 in the solution? (b) What is the ph of the solution? 27. Predict whether the solutions of each of the following salts will be acidic, basic, or neutral. If the solution is acidic or basic, write the hydrolysis reaction. (a) KlO 3 (b) NH 4 NO 3 (c) Na 2 H 3 O 2 (d) NH 4 N 28. A solution is M in ammonium bromide. (a) Write the equation for the hydrolysis of ammonium bromide. (b) Write the equilibrium constant expression for the reaction. (c) alculate the ph of the solution. 29. A solution is 0.60 M in potassiium chlorite. (a) Write the equation for the hydrolysis of potassium chlorite. (b) Write the equilibrium constant expression for the reaction. (c) alculate the ph of the solution. 30. A solution M in sodium hypochlorite has a ph of (a) Write the equation for the hydrolysis of sodium hypochlorite. (b) Write the equilibrium constant expression for the reaction. (c) alculate the value for the hydrolysis constant. (d) alculate the acid ionization constant for hypochlorous acid. ompare your answer with the value from Handout 3. HOMEWORK 1R ANSWERS 1. (a) K c = [O] 2 [O 2 ] M K p = p 2 O p O2 atm [O 2 ] 2 p O2 2 (b) K c = [Hl] 3 [P(NH 2 ) 3 ] none K p = p Hl 3 p P(NH2)3 none [Pl 3 ][NH 3 ] 3 p Pl3 p NH3 3 (e) K c = [O][H 2 ] M K p = p O p H2 atm [H 2 O] p H2O 2. (a) 216 (b) x (a) reverse (b) forward (c) equilibrium 5. (a) atm (b) 3.5 x 10 7 (c) M

14 6. (a) M (b) 9.77 M 1 (c) 5.72 g x 10 3 atm atm x M each atm, 3.53 x 10 2 M atm 12. (a) M u 2+, M NH 3 (b) M u(nh 3 ) 4 2+ (c) M u 2+, M NH 3 (d) 6.7 x (a) none, none (b) right, higher (c) right, higher (d) right, lower (e) left, lower (f) none, none 14. (a) none, same (b) left, same (c) left, same (d) right, higher (e) none, same (f) none, same 15. (a) Ag 2 O 3 (s) 2Ag + (aq) + O 3 2 (aq) (b) Ag 2 O 3 (s) + 2l (aq) 2Agl (s) + O 3 2 (aq) (c) Ag 2 O 3 (s) + 2H + (aq) 2Ag + (aq) + H 2 O (l) + O 2 (g) 16. (a) HlO 2 + H 2 O H 3 O + + lo 2 K a = [H 3 O + ][lo 2 ] [HlO 2 ] (b) NH H 2 O H 3 O + + NH 3 K a = [H 3 O + ][NH 3 ] [NH + 4 ] 17. HS, H 2 S and HSO 3 (tie), H 2 SO 3, H 2 SO H 2 O, 5 H 5 NH +, H 3 H 5 O 2, HNO 2, HBr 19. (a) (H 3 ) 3 N + H 2 O (H 3 ) 3 NH + + OH K b = [(H 3 ) 3 NH + ][OH ] [(H 3 ) 3 N] (b) 6 H 5 O + H 2 O 6 H 5 OH + OH K b = [ 6 H 5 OH][OH ] [ 6 H 5 O ] 20. H 2 NNH 2, NH 3, H 3 NH 2, 21. H 2 O, F, HO 2 3, O (a) 1.82 (b) 12.48

15 23. (a) HO 2 H + H 2 O H 3 O + + HO 2 (b) K a = [H 3 O + ][HO 2 ] [HO 2 H] (c) 1.7 x 10 4 (d) (a) 6 H 5 O 2 H + H 2 O H 3 O H 5 O 2 (b) K a = [H 3 O + ][ 6 H 5 O 2 ] [ 6 H 5 O 2 H] (c) 2.59 (d) 2.5% 25. (a) 4.9 x 10 4 M (b) (a) M H 3 O +, M H 6 H 6 O 6, 1.6 x M 6 H 6 O 6 2, M H 2 6 H 6 O 6 (b) (a) neutral (b) acidic NH H 2 O H 3 O + + NH 3 (c) basic 2 H 3 O 2 + H 2 O H 2 H 3 O 2 + OH (d) basic NH H 2 O H 3 O + + NH 3 K a = 5.6 x N + H 2 O HN + OH K b = 1.6 x 10 5 (bigger constant, so stronger) 28. (a) NH H 2 O H 3 O + + NH 3 (b) K a = [H 3 O + ][NH 3 ] [NH + 4 ] (c) (a) lo 2 + H 2 O HlO 2 + OH (b) K b = [HlO 2 ][OH ] [lo 2 ] (c) (a) lo + H 2 O HlO + OH (b) K b = [HlO][OH ] [lo ] (c) 2.9 x 10 7 (d) 3.5 x 10 8