Question

find the concentration of unknown #16.

Titration of Unknown #16: Buret Reading 0 mL 0.51 mL 1.20ml pH Value 1.92 1.92 3.78 1.75mL 6.07 2.26 mL 6.49 7.18 2.80 mL 3.31 mL 8.94 3.83 mL 9.49 4.32 mL 9.82 4.75 mL 10.07 5.01 mL 10.33 5.23 mL 10.53 5.55 mL 10.7 5.92 mL 10.93 6.10 mL 11.05 6.42 mL 11.24 6.71 mL 11.39 7.01 mL 11.59 7.21 mL 11.7 7.71 mL 11.85 8.01 mL 11.9 8.23 mL 11.99 12.03 8.41 mL 8.52 mL 12.08 8.64 mL 12.09 8.75 mL 12.1 9.01 mL 12.11 9.25 mL 11.31 9.41 mL 11.35 9.52 mL 11.39 9.72 mL 11.47 9.80 mL 11.49 9.91 mL 11.54 10.01 mL 11.57 10.11 mL 10.23 mL 10.41 mL 11.59 11.61 11.65 10.50 mL 11.68 10.61 mL 11.7

Answer 1

Average pH = 9.374 9.4 +9.38 - 28.15 - 9.383 Also, we know that pH = -log [ht] 9.383 = - log [ht] [ht] = 0.2415 The concentration of Ht is 0. 2415 therefore concentration of unknown is also equal to 0.2415