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Quiz 1. What is the equilibrium pH of a 0.175 M solution of the diprotic 1,5-pentanedioic acid? pK a1 = 4.345 and pK a2 = 5.422. Show your work. a. 11.4 b. 2.6 c. 3.6 d. 2.81 x 10 -3
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Quiz 1. What is the equilibrium pH of a 0.175 M solution of the diprotic 1,5-pentanedioic acid? pKa1 = 4.345 and pKa2 = 5.422. Show your work. a. 11.4 b. 2.6 c. 3.6 d. 2.81 x 10-3 2. From problem 1 above, what is the equilibrium concentration of the base form of 1,5-pentanedioic acid? a. 2.8 x 10-3 M b. 0.175 M c. 4.7 x 10-11 M d. 3.8 x 10-6
Quiz 3. Consider a buffer solution made from the weak base A2- with pKa1 = 4.5 and pKa2 = 9.0. In a buffer solution with pH = 8.7, which Henderson-Hasselbalch equation should be used for calculations? a. b. c.d. 4. Consider a buffer where the [HA] + [A-] = 0.250 M and [A-] / [HA] = 2.00. What is [HA]? Show your work. a. 0.125 M b. 8.33 x 10-2 M c. 0.167 M d. none of these