Consider the acid, HA, where A is a singly-charged anion. 0.018 moles of the acid was added to 750mL of pure water at 25°C. The final pH of the solution was measured to be 1.6. What is the pKa of the acid HA?
A) 2.4
B) 3.2
C) 4.8
D) 5.6