Question

1. Phosphoric acid, H3PO4 is a triprotic acid with pKsı = 2.14 and pKa = 7.20 and pkas 12.38. Draw the titration curve predicted for 0.1 M phosphoric acid titrated by 0.1 M NaOH. (Assume the volume of acid is 20. mL) 2. The pKb of the acetate ion is 9.25. a. Using this information, calculate the pKa of acetic acid. b. Using the Henderson-Hasselbalch equation, calculate the ratio of the concentration of acetate to acetic acid required to produce a buffer solution with pH 4.10 c. Calculate the mass of sodium acetate that would need to be added to 1L of 0.100 M acetic acid to buffer solution having pH 4.10. You may assume that the addition of sodium acetate does not appreciably change the volume of solution. 3. Glutamic acid: Glutamic acid is a triprotic amino acid with pKa values of 2.19, 4.25, and 9.67 At very low pH, glutamic acid has a +1 charge and at very high pH glutamic acid has a charge of -2. NH2 Predict the predominant charge on glutamic acid at each pH in the following list and then draw the form of glutamic acid in the solution. This neutral form only exists in the solid state. Figure 10-4 Drawings: a. At pH = 1.00, charge a. b. At pH 4.00, chargeb. c. At pH-8.00, chargec. d. d. At pH 12.00, charge

Answer 1

14 29 30 31 plu 60ML OnM 2.A) pra of aceh, c acid= 14 ch te Lacehcacid]

Lacetata0 224 Taceh'c auid ILX 0.02 2 4 (N) mse レof o. 0224 (N) Sodium acetate= e0:6224 Sodium aco扣te. 134 g