<p> Titrations and Chemical Analysis 1. In a titration, 24.0 mL of 0.100 M NaOH was needed to react with 20.00 mL of HCl solution. What is the molarity of the acid? 0.12 M 2. A 10.00 mL sample of vinegar, containing acetic acid, HC2H3O2(aq), was titrated using 0.500 M NaOH solution. The titration required 13.40 mL of the base. a) What was the molar concentration of acetic acid in the vinegar? 0.67 M b) What was the W/V percent concentration of the acetic acid in the vinegar? (CH3COOH = 60.06 g/mol 4.025 % 3. Lactic acid, HC3H5O3, is a monoprotic acid that is formed when milk sours. A 20.0 mL sample of a solution of lactic acid required 18.35 mL of 0.160 M NaOH to reach an end point in a titration. How many moles of lactic acid were in the sample? 0.00294 moles 5. Aspirin is a monoprotic acid called acetylsalicylic acid. This formula is HC9H7O4(180.17 g.mol). A certain pain reliever was analyzed for aspirin by dissolving a 250 mg tablet in water and titrating it with 0.0300 M KOH solution. The titration required 29.40 mL of base. What is the percentage by weight of aspirin in the pill? 63.56%</p><p>6. A student prepared a solution of hydrochloric acid that was approximately 0.1 M and wished to determine its precise concentration. A 25.00 mL portion of the HCl solution was transferred to a flask, and after a few drops of indicator solution were added, the HCl soltuion was titrated with 0.0775 M NaOH solution. The titration required exactly 37.46 mL of the standard NaOH solutoin. What was the exact molarity of the HCl solution? 7. A solution of ammonia in water was analyzed by titrating the ammonia with hydrochloric acid. The net ionic reaction is: +1 +1 NH3(aq) + H3O (aq) -----> NH4 (aq) + H2O(l) In the analysis, a 5.00 grams sample of the ammonia solution was placed in a flask and titrated with 1.00 M HCl, using an appropriate indicator. The titration required 29.86 mL of the HCl solution. What is the W/V percent composition of the NH3 in the ammonia solution?</p><p>8. In a titration, a sample of H2SO4 solution having a volume of 15.00 mL required 36.42 mL of 0.147 M NaOH solution for complete neutralization. What is the molarity of the H2SO4 solution? 9. "Stomach acid" is hydrochloric acid. A sample of gastric juices having a volume of 5.00 mL required 11.00 mL of 0.0100 M KOH solution for neutralization in a titration. What was the molar concentration of HCl in this fluid? What was the W/V percent composition of HCl in the gastric fluid?</p><p>10. A certain toilet bowl cleaner uses NaHSO4 as its active ingredient. In an analysis, 0.500 grams of the cleaner was dissolved in 30.0 mL of distilled water and required 24.60 mL of 0.105 M NaOH for complete neutralization in a titration. The net ionic equation for the reaction is: -1 -1 -2 HSO4 (aq) + OH (aq) ------> H2O(l) + SO4 (aq) 11. How many grams of Ca(OH)2 would be needed to completely neutralize 42.6 grams of H3PO4?</p><p>12. A solid sample weighing 0.950 grams contained strontium chloride and some inert impurities. It was dissolved in water and treated with 25.00 mL of 0.25 M AgNO3 solution to give a precipitate of silver chloride. The excess silver ions in the solution were titrated with 8.00 mL of 0.210 potassium thiocyanate (KSCN) according to the following equation: +1 -1 Ag (aq) + SCN (aq) ------> AgSCN(s) What percentage of strontium chloride was present in the original sample?</p>