37. A sodium salt (NaHA, 4.1 mole) is dissolved in 1.0 L water. The solution's pH is 5.0 after some acid
or base is added in the solution. What is the concentration of HA at pH 5.0 if the Kai and Ka2 of H2A are
1 x 109 and 5 x 10-?, respectively? A) 0.1 M; B) 0.2 M; C) 0.5 M; D) 1.0 M; E) 2.0 M
38. Continued from the previous question. What is the concentration of A2-
A) 0.1 M; B) 0.2 M; C) 0.5 M; D) 1.0 M; E) 2.0 M