Worksheet 1 Name Date Per. Acid Base Theories 1) List at least three characteristic properties of acids and three of bases. ACIDS a) BASES a) b) b) c) c) 2) According to the Arrhenius theory, a) what is an acid? b) what is a base? 3) According to the Bronsted-Lowry theory, a) what is an acid? b) what is a base? 4) According to the Lewis theory, a) what is an acid? b) what is a base? 5) In each of the reactions below, identify the acid, base, conjugate acid and conjugate base. a) NH4+ + CN- b) HS- + HSO4- c) NH3 + HBr d) NH4+ + OH- + NH3 H 2S + SO42- NH4+ + Br- NH3 + H 2O HCN 6) List the conjugate acids of: (that means the following would behave like bases…) a) H2O b) NH3 c) OHd) HPO42- 7) List the conjugate bases of: (that means the following would behave like acids…) a) H2O b) HSc) HCl d) NH4+ 8) For each of the following acid-base combinations, write (1) balanced formula unit equation, (2) total ionic equation, and (3) net ionic equation. a) 1) 2HBr(aq) + Sr(OH)2(aq) 2) 3) b) 1) 2HNO3(aq) + Ba(OH)2(aq) 2) 3) c) 1) H2SO4(aq) + 2KOH(aq) 2) 3) d) 1) 2HI(aq) +Ca(OH)2(aq) 2) 3) e) 1) HClO4(aq) + LiOH(aq) 2) 3) Worksheet 2: pH and pOH The pH of a solution indicates how acidic or basic that solution is. pH range of 0-7 acidic 7 neutral 7-14 basic Since [H+]·[OH-] = 10-14 at 25C, if [H+] is known, the [OH-] can be calculated and vice versa. pH = -log [H+] So if [H+] = 10-6 M, pH = 6 pOH = -log [OH ] So if [OH-] = 10-8, pOH = 8 Together, pH + pOH = 14. Complete the following chart: [H+] 1. 10-5 M 2. pH 5 10-4 M 10-2 M 5. 11 6. 12 10-5 M 7. 8. 10-11 M 9. 10. pOH 9 7 3. 4. [OH-] 10-9 M 13 6 Acidic or Basic Acidic pH and pOH CONTINUED Calculate the pH of the solutions below. 1. 0.01 M HCl 2. 0.0010 M NaOH 3. 0.050 M NaOH 4. 0.030 M HBr 5. 0.150 M KOH 6. 2.0 M HC2H3O2 (Assume 5.0% dissociation.) 7. 3.0 M HF (Assume 10.0% dissociation.) 8. 0.50 M HNO3 9. 2.50 M NH4OH (Assume 5.00% dissociation.) 10. 5.0 M HNO2 (Assume 1.0% dissociation.) Worksheet 3: pH and pOH Problem Set 1) What is the pH of each of the following solutions? a) 0.00015 M HCl b) 0.000 000 06 M HCl c) 0.031 M HCl 2) What is the pH of a solution if [H3O+] = 5.4 x 10-8 M? 3) The pH of a solution is determined to be 9.00. What is the [H3O+]? 4) The pH of a solution is determined to be 4.56. What is the [H3O+]? 5) What is the pH of each of the following solutions? a) 0.025 M NaOH b) 1.13 M NaOH c) 0.000051 M NaOH 6) Determine the pH of the following solutions. a) 0.000014 M HNO3 c) 2.50 x 10-6 M HNO3 b) 0.0045 M HCl d) 8.75 x 10-3 M HCl 7) Determine the [H3O+] for the following solutions: a) drain cleaner with a pH of 13.2 b) human blood with a pH of 7.4 c) ammonia with a pH of 11.3 d) apple juice with a pH of 3.5 8) Determine the pH of the following base solutions: a) 0.00045 M KOH c) 2.80 x 10-4 M NaOH b) 0.685 M KOH d) 3.1 x 10-11 M NaOH 9) Determine the [H3O+] and the [OH-] of the following solutions: a) a solution with a pH of 5.85. b) a solution with pH of 11.3. c) a solution with a pH of 1.5. 10) What is the pH and the pOH of the following solutions? a) 0.000005 M solution of HBr (acid) b) 2.45 x 10-3 M solution of KOH (base) 11) The pH of sea water is 8.3. What is the [OH-] and the [H3O+] of sea water? 12) Calculate the pH, pOH, [OH-] and [H3O+] for the following solutions: a) 0.00082 M HNO3 c) 1.5 x 10-4 M KOH b) strawberries with a pH = 3.55 d) soap with a pH of 10.8 Worksheet 4: Titration Acid-base titration involves the gradual addition of acids and bases to one another, generally for the purpose of determining reacting volumes or concentrations. In a laboratory titration, 1M HCl was gradually added to 50 mL of 1M NaOH. The pH was monitored throughout the analysis, and the following readings were obtained. VOLUME OF HCl ADDED (mL) 0 pH OF SOLUTION 14.0 5 13.9 10 13.8 15 13.7 20 13.6 30 13.4 40 13.0 45 12.4 49 11.7 50 7.0 51 2.3 55 1.6 60 1.0 75 0.7 100 0.64 Plot these data on the grid above, and then answer the following questions. 1. What volume of 1.0 M HCl was required to reach the equivalent point? 2. How would the graph differ if the concentration of titrating HCl were increased to 2.0 M? 3. List an indicator that could be used to recognize the equivalence point of this titration. Describe the color changes that the solution would undergo with the addition of HCl. Titration Practice Problems: solve the following problems on a separate piece of paper or the back of this worksheet. 1. What volume of 0.275 M hydrochloric acid solution reacts with 36.4 mL of 0.150 M sodium hydroxide solution? HCl + NaOH NaCl + H2O 2. What volume of 0.112 M NaOH solution would be required to react with 25.3 mL of 0.400 M H 2SO4 solution? H2SO4 + 2NaOH Na2SO4 + 2H2O 3. A 0.08964 M solution of NaOH was used to titrate a solution of unknown concentration of HCl. A 30.00 mL sample of the HCl solution required 24.21 mL of the NaOH solution for complete reaction. What is the molarity of the HCl solution? (see #1 for equation) 4. A 34.53 mL sample of a solution of sulfuric acid, H 2SO4, reacts with 27.86 mL of 0.08964 M NaOH solution. Calculate the molarity and normality of the sulfuric acid solution. (see #2 for equation) Worksheet 5: H Chem Study Guide: Acids and Bases 1) List at least three characteristic properties of acids and three of bases. 2) Identify the acid, base, conjugate acid, and conjugate base in the following reactions: a) HNO3 + H2O H3O+ + NO3b) H2C2O4 + CH3NH2 HC2O4- + CH3NH3+ c) NH4+ + H2O NH3 + H3O+ 3) Complete and balance the following neutralization / acid-base reactions: a) NaOH + H2CO3 b) H2SO4 + Ba(OH) 2 c) H2S + KOH d) Al(OH) 3 + HBr 4) Write a balanced: (1) formula unit, (2) total ionic, and (3) net ionic equation for each of the following acid-base reactions: a) KOH + H2SO4 b) HNO3 + Ba(OH)2 c) H2CO3 + Al(OH)3 d) Ca(OH)2 + HCl 5) Given a salt, predict an acid-base pair which would produce the salt: a) Al2(SO4)3 c) CaCl2 b) NH4F d) KBr 6) Solve the following acid-base titration problems: a) What is the molarity of sodium hydroxide, NaOH, if 59.0 mL of the solution is titrated to the endpoint with 24.0 mL of 0.75 M sulfuric acid (H2SO4)? (Hint: write the balanced equation first!) b) A 55.6 mL sample of HCl is titrated with 79.9 mL of a 1.25 M solution of NaOH. What is the molarity of the HCl? 7) If you have a 1.0 M solution of NaOH and a solution of HCl with an unknown concentration, explain how you would use titration to determine the concentration of the HCl solution. (Explain the steps) 8) Perform the following molarity/normality problems: a) What is the normality of a 5.0 M phosphoric acid (H3PO4) solution? b) Find the normality of 5.6 g HBr in 450.0 mL of solution. c) If 45.0 mL of 0.30 N H2SO4 are neutralized by 75.0 mL of NaOH, find the normality of the NaOH. d) A 43.7 mL sample of Ba(OH) 2 is neutralized by 33.5 mL of 0.86 M HCl. What is the normality and molarity of the Ba(OH) 2 solution? 9) Calculate the pH and pOH of the following solutions: a) [H+] = 1 x 10-6 M c) [H+] = 7.4 x 10-8 M e) [H+] = 3.22 x 10-3 M b) [OH-] = 1 x 10-9 M d) [OH-] = 9.9 x 10-11 M f) [OH-] = 5.76 x 10-2 M 10) Calculate [H+] and [OH-] for the following solutions: a) a solution with pH = 11 c) a solution with pH = 2.45 e) a solution with pOH = 1.3 b) a solution with pH = 8.5 d) a solution with pOH = 7 f) a solution with pOH = 12.6