Determination of the Concentration of Acetic Acid in Vinegar

Determination of the Concent symmetryn of acetic Acid in acetum Lab Exercise 4 CHEM 1106 9/19/12 mean Standardize a atomic number 11 hydrated oxide solution using a primary standard loony toons. Determine the chiliad and the percent by dope of acetic corrosive in vinegar by titration with the standardized sodium hydroxide solution. Introduction acetum is a dilute solution containing acetic sulphurous. Since vinegar has a low pH, it can be measured with a base.Titration is a method used in order to ascertain the amount of a constituent in a solution by measuring the tawdriness of a known concentration of a reagent involve to complete a reaction with it, typically using a burette. The comparing point of a titration occurs when chemically equivalent amounts of acid and base are present. In this experiment, the equivalence point occurs when the breakwateres of acid in the solution equals the gram groineculees of base added in the titration. A rapid change in pH with the sm all addition of acid or base is the indicator for acid-base equivalency.Accompanying material Vinegar electric battery Statement of the ProblemUsing a pH meter and a graph of pH plotted versus the mass of base added, the equivalence point can be accurately found by finding the point that is in the midsection of the vertical part of the arc. Once the equivalence point of the titration is known, the concentration of the sodium hydroxide can be determined. Sodium hydroxide is used to titrate vinegar so that the concentration of the vinegar is determined. The percentage of acetic acid in solution can be determined from the concentration of the vinegar. social function spokesperson A calibration of a Sodium Hydroxide event 1. Prepare 150 mL of some 0. M sodium hydroxide solution from solid NaOH. The solution can be prepared in a beaker, it is not necessary to use a graduated piston chamber or a volumetric flask because the NaOH solution will be standardized. 2. Weigh a 150-mL be aker and record the atomic pile to the nearest 0. 001 g. Add approximately 0. 5 grams of potassium hydrogen phthalate (KHP) to the beaker. Record the muckle of the beaker and KHP to the nearest 0. 001 g. organise the mass of KHP by difference and record it. Add approximately 50 mL of distilled water to the beaker. Stir the solution until the KHP has dissolved completely. 3.Record a titration curve using the MeasureNet pH probe and drop counter. (See Appendix F) 4. Repeat travel 2 and 3. 5. From the plots, determine the volume of NaOH required to neutralize the KHP solution in each titration. Record the volumes. 6. Calculate the groinarity of sodium hydroxide. Part B Determination of Acetic Acid Concentration in Vinegar 7. expatriation 2. 0 mL of vinegar to a clean, dry 150 mL beaker using a 10-mL volumetric pipet. Add sufficient water, 50 mL, to thwart the pH electrode tip during the titration. 8. Record a titration curve using the MeasureNet pH probe and drop counter. See A ppendix F) 9. From the plots, determine the volume of NaOH required to neutralize vinegar in each titration. Record the volumes. 10. Calculate the molarity of acetic acid in vinegar. 11. Calculate the percent by mass of acetic acid in vinegar. Data Part A Standardization of a Sodium Hydroxide Solution Mass of beaker97. 47 g Mass of beaker + KHP97. 99 g Mass of KHP0. 52 g loudness of NaOH to neutralize the KHP solution7. 755 mL thousand of sodium hydroxide 0. 535 M NaOH Part B Determination of the Concentration of Acetic Acid in Vinegar Volume of NaOH required to neutralize vinegar3. 18 mL Molarity of acetic acid in vinegar0. 8515 M CH3COOH portion by mass of acetic acid in vinegar5. 115% Equations (1) Molarity (M) = moles of solute/liter of solution (2) Percent solute= (grams of solute/grams of solution) x 100% (3) NaOH (aq) + CH3COOH (aq) NaCH3CO2 (aq) + H2O (l) (4) pH = -logH3O+ (5) KHC8H4O4 (aq) + NaOH (aq) KNaC8H4O (aq) + H2O (l) Calculations Part A Standardization of a So dium Hydroxide Solution Calculate the mass of KHP (Mass of Beaker + KHP) Mass of Beaker = Mass of KHP 97. 99g 97. 47g = 0. 52g Calculate the molarity of sodium hydroxideMoles of KHP = g/MW = 0. 52g/204. 22g = 0. 002546 mol KHP Equation 5 = 11 ratio 0. 002546 mol KHP x 1 mol NaOH/1mol KHP = 0. 002546 mol NaOH Equation 1 = 0. 002546 mol/0. 004755 L = 0. 535 M NaOH Part B Determination of the Concentration of Acetic Acid in Vinegar Calculate the molarity of acetic acid in vinegar 3. 318 mL/1000 = 0. 00318 L NaOH 0. 00318 L NaOH x 0. 535 mol/1L NaOH = 0. 001703 mol NaOH Equation 3 = 11 ratio 0. 001703 mol NaOH x 1 mol CH3COOH/1 mol NaOH = 0. 001703 mol CH3COOH 2. 0 mL CH3COOH/1000 = 0. 0020 L CH3COOH Equation 1 = 0. 01703 mol CH3COOH/0. 0020 L soln. = 0. 8515 M CH3COOH Calculate the percent by mass of acetic acid in vinegar 0. 0020 L CH3COOH x 0. 8515/1 L soln. = 0. 001703 mol CH3COOH 0. 001703 mol CH3COOH x (60. 06g CH3COOH/1 mol CH3COOH) = 0. 1023g CH3COOH 2. 0 mL CH3COOH x (1g CH3 COOH/1 mol CH3COOH) = 2. 0 mL CH3COOH soln. Equation 2 of CH3COOH = (0. 1023 g CH3COOH/2. 0g CH3COOH) x 100% = 5. 115% Final Answer Molarity of vinegar0. 8515 M CH3COOH Percent mass5. 115% CH3COOH From the plots determine the volume of NaOH required to neutralize the KHP solution in each titration.