Watch the analysis videos to find the experimental

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Watch the analysis videos to find the experimental measurements (equivalence volume, half-equivalence volume and pH) needed for data table 2, and the complete the remainingcalculations.Data Table 2: Titrating the Unknown AcidSample ID of unknown weak acid12Concentration of NaOH solution (M)mass of unknown acid,g(Use taring feature)0.1630.172volume of NaOH solution required to reachequivalence point (in mL)volume of NaOH solution required to reach half-equivalence point (in mL)pH at half-equivalence pointpKaof unknown weak acidnumber of moles of NaOH required to reachequivalence point (mol)number of moles of unknown acid titrated (mol)
11Identification of a Weak Acid by TitrimetryREPORTGroup Portion:Part I. Preparing a Standardized NaOH solution.1.Show the calculation for the preparation of 300 mL of 0.05 M NaOH from 2 M NaOH stocksolution.2.Determine the molarity of the NaOH titrant for each titration in the standardization of NaOH(Data table 1) and calculate the average. Show your work for one of the concentrationcalculations.Part II. Titrating the Unknown Acids3.Use the equivalence-point volume and average NaOH concentrations to determine thenumber of moles of NaOH required to reach the equivalence point and from that value, thenumber of moles of unknown acids titrated. Show both calculations.4.Calculate the molar mass of the unknown acid for each unknown. Show your work.5.Record the names, pKa, and molar masses of your unknown acids, and list the pKaand molarmass of the acid from Table 1 that best matches each unknown.Unknown 1ExperimentalTheoreticala.pKa________________________________b.Molar mass________________________________c.Name of acid________________Unknown 2ExperimentalTheoreticald.pKa________________________________e.Molar mass________________________________f.Name of acid________________6.Submit typed copies of Data Tables 1 and 2.7.Assuming that you correctly identified the unknown acids, calculate the percent error in yourexperimental determination of each of the following. (See Appendix A for the formula forpercent error if you don’t remember it).a.molar mass of the unknown acid 1b.pKaof the unknown acid 1c.molar mass of the unknown acid 2d.pKaof the unknown acid 2
128.Compare the amount of undissociated acid (HA) and dissociated acid (A-), and compare theamount of H+to OH-throughout the titration of a weak acid by a strong base described by thetitration curve below ([A]: before the ½ equivalence point; [B] at the ½ equivalence point;[C] after the ½ equivalence point but before the equivalence point; [D] at the equivalencepoint; [E] after the equivalence point). (For region C, the relative concentrations of [H+] and[OH-] swap places. Explain which way they change).9.If you prepared a solution by adding equal numbers of moles of sodium sulfite (Na2SO3which produces the A-in solution) and sodium hydrogen sulfite (NaHSO3which producesthe HA in solution) to 50 mL of water, what would be the pH of the solution? The relevantacid dissociation equation is the following:(Hint: Identify the acid and the base in thefollowing equation. Use what you learned in Question 8 and Table 1 on pg. 2.)HSO3H2O+-2-+H3O+SO3

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Term
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bauer
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