Procedure A student used a pH meter to collect data for the titration of an unknown concentration of ethanoic (acetic) acid with a 0.150 mol/L solution of sodium hydroxide. The data table from the investigation is shown in the table below. & Enter the data from the table into a spreadsheet program. Use the program to plot the results, with pH on the vertical axis and volume of base added on the horizontal axis. Make sure you enter labels for each axis, and provide a suitable title for your graph. Print your graph. Titration of Ethanoic Acid with Sodium Hydroxide Volume of ethanoic acid = 25.00 ml [NaOH] = 0.150 mol/L b On your graph, shade the buffer region. Identify the pH range of an indicator suitable for this titration. Name two indicators that would have endpoints suitable for this Volume of NaOH(aq) Added (mL) pH titration. None 2.83 C The titration curve should show a steep change in pH near the equivalence point. Choose a point halfway along the portion of rapid change on the graph. Label this the equivalence point. 2.00 3.84 4.11 4.20 7.98 4.64 11.95 5.03 Analysis a From your graph, determine the pH and volume of base added at the equivalence point. 14.08 5.27 16.05 5.61 17.00 5.90 b Calculate the concentration of the ethanoic (acetic) acid solution. 17.21 6.00 C. Explain why the pH at the equivalence point is not 7, the pH of neutral water. 17.39 6.09 17.62 6.23 d What ions and molecules are in solution well before the equivalence point, such as at 10 mL of base added? How does this compare with the solution well after the equivalence point, such as at 20 ml of base added? 17.99 6.74 18.18 8.80 18.39 10.92 18.80 12.24 20.00 12.56 22.03 12.69

a) In a NaOH and HCl titration lab: Suppose you add 40 ml of water instead of the 45 mL. How will this affect the calculations for the molarity of the HCI? (In this case, the molarity of HCl turned out to be 0.559 mol/L). While being specific. Explain why it will not matter or it will make the molarity high or it will make the molarity low. b) if you disregard the instructions to titrate until a persistent blue endpoint is reached and instead conclude the titration at the initial appearance of blue, describe the impact on the reported molarity of the CoC12 solution. Provide specific details and specify whether the reported molarity will be higher, lower, or remain unaffected.

Incorrect Your answer is incorrect A chemistry student weighs out 0.414 g of citric acid (H,C,H,O.), a triprotic acid, into a 250. mL. volumetric flask and dilutes to the mark with distilled water. He plans to titrate the acid with 0.0500 M NaOH solution. Calculate the volume of NaOH solution the student will need to add to reach the final equivalence point. Be sure your answer has the correct number of significant digits. 12.9 ml.

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