AQUEOUS EQUILIBRIUM CONSTANTS APPENDIX TABLE D. 1 Dissociation Constants for Acids at 25 °C Кл K2 Formula 1.8 x 10 5 Name CH,COOH (or HC,H,O2) 5.6 x 10 3 1.0 X 10-7 Acetic acid 30X 1012 Arsenic acid H3ASO4 5.1 x 10 10 H3ASO3 8.0 x 10 5 1.6 x 10 12 Arsenous acid Ascorbic acid H2C,H,O6 6.3 x 10-5 Benzoic acid CHSCOOH (or HC,H5O2) 5.8 x 10-10 Boric acid HаВОЗ 1.5 X 10-5 TA Butanoic acid C3H,COOH (or HC4H,O2) 4.3 x 10-7 5.6 X 10-11 Carbonic acid Н.СОЗ 1.4 X 10 3 Chloroacetic acid CH2CICOOH (or HC2H2O2CI) 1.1 X 10-2 Chlorous acid HCIO2 7.4 X 10-4 1.7 X 10-5 Citric acid HOOCC(OH)(CH2COOH)2 (or H3C,H5O7) 4.0 x 107 3.5 x 10 4 Cyanic acid HCNO НСООН (or НСНО2) 1.8 X 10-4 Formic acid Hydroazoic acid HN3 1.9 x 10-5 Hydrocyanic acid 4.9 x 10-10 HCN Hydrofluoric acid 6.8 X 10-4 HF Hydrogen chromate ion HCRO4 3.0 x 10-7 Hydrogen peroxide H2O2 2.4 X 10-12 Hydrogen selenate ion HSEO4 2.2 X 10-2 Hydrogen sulfide H2S 9.5 x 10-8 1 x 10-19 Hypobromous acid HBRO 2.5 x 10-9 Hypochlorous acid HCIO 3.0 x 10-8 Hypoiodous acid HIO 2.3 x 10-11 Iodic acid HIO3 1.7 x 10-1 Lactic acid CH3CH(OH)COOH (or HC3H;O3) 1.4 X 10-4 Malonic acid CH2(COOH)2 (or H2C3H2O4) 1.5 X 10-3 2.0 x 10-6 Nitrous acid HNO2 4.5 X 10-4 Oxalic acid (CООН)2 (or HС,О) 5.9 x 10-2 6.4 x 10-5 Paraperiodic acid H;IO6 2.8 x 10-2 5.3 x 10-9 Phenol C,H3OH (or HC,H;O) 1.3 x 10-10 Phosphoric acid HЭРОД 7.5 x 10-3 6.2 x 10-8 4.2 x 10 Propionic acid CЭН,СООН (or НС3H,02) 1.3 x 10-5 Pyrophosphoric acid НАР.О, 3.0 x 10-2 4.4 x 10-3 2.1 x 10 Selenous acid H,SeO3 2.3 X 10-3 5.3 x 10-9 Sulfuric acid H2SO4 Strong acid 1.2 x 10-2 Sulfurous acid H,SO3 1.7 x 10-2 6.4 x 10-8 Tartaric acid HOOC(CHOH),СООН (or H,C,Н,О6) 1.0 X 10-3 1092 (C,H5COOH) and an ate (C,H5COONA). solution prior to ad. grams of sodium be buffer? Neglect the the sodium benzoa CHAPTER 17 Additional Aspects of Aqueous Equilibria 760 trimethylamine, (CH3)3N, and 0.10 M in trimethylammo- nium chloride, (CH3)3NHƠI; (c) a solution that is made by mixing 50.0 mL of 0.15 M acetic acid and 50.0 mnL of 0.20 M sodium acetate. 17.27 A buffer contains sodium acetate in (a) a solution that is 0.250 M in sodium formate (HCOONA) and 0.100 M in formic acid (HCOOH), (b) a solution that is 0.510 M in pyridine (C,H,N) and 0.450 M in pyridinium chloride (CsH;NHCI), (c) a solution that is made by com- bining 55 mL of 0.050 M hydrofluoric acid with 125 mL of 0.10 M sodium fluoride. 17.16 Use information from Appendix D to calculate the pH of (b) What is the pH mol of KOH? (c) W tion of 0.02 mol o 17.28 A buffer contains and 0.10 mol of so 17.17 (a) Calculate the percent ionization of 0.0075 M butanoic 1.5 x 10-5). (b) Calculate the percent ioniza- (a) What is the p buffer after the a acid (Ka tion of 0.0075 M butanoic acid in a solution containing 0.085 M sodium butanoate. %3D the pH of the bu 17.29 (a) What is the r: (b) What is the marathon runn 17.18 (a) Calculate the percent ionization of 0.125 M lactic acia = 1.4 × 10¬4). (b) Calculate the percent ionization of 0.125 M lactic acid in a solution containing 0.0075 M so- dium lactate. (Ka %3D 17.30 A buffer, consis the pH of physi Buffers (Section 17.2) also use this bu in which the m and 8.0 g of Na 17.19 Which of the following solutions is a buffer? (a) 0.10 M ixG CH3COOH and 0.10 MCH3COONA, (b) 0.10 M CH3COOH, (c) 0.10 M HCl and 0.10 M NaCI, (d) both a and c, (e) all of a, b, and c. 17.20 Which of the following solutions is a buffer? (a) A solu- tion made by mixing 100 mL of 0.100 M CH3COOH and 50 mL of 0.100 M NaOH, (b) a solution made by mixing 100 mL of 0.100 M CH;COOH and 500 mL of 0.100 M NaOH, (c) A solution made by mixing 100 mL of 0.100 M CH3COOH and 50 mL of 0.100 M HCI, (d) A solution made by mixing 100 mL of 0.100 M CH3COOK and 50 mL of 0.100 M KCI. 17.31 You have to pi following 0.10 H3PO4, HCOC tions would y would you us 17.32 You have to p following 0.1 CH,COОН, tions would 17.21 (a) Calculate the pH of a buffer that is 0.12 M in lactic acid and 0.11 M in sodium lactate. (b) Calculate the pH of a buf- fer formed by mixing 85 mL of 0.13 M lactic acid with 95 mL of 0.15 M sodium lactate. would you u Acid-Base Titra 17.22 (a) Calculate the pH of a buffer that is 0.105 M in NaHCO3 and 0.125 M in Na2CO3. (b) Calculate the pH of a solution formed by mixing 65 mL of 0.20 M NaHCO3 with 75 mL of 0.15 M Na CO3. 17.23 A buffer is prepared by adding 20.0 g of sodium ace- tate (CH3COONA) to 500 mL of a 0.150 M acetic acid (CH;COOH) solution. (a) Determine the pH of the buffer. (b) Write the complete ionic equation for the reaction that 17.33 The accomp monoproti (b) What i of each titr a 0.100 M mate the p Occurs when a few drops of hydroghl