Calculate the PH of a 0 $\times$ 10^-5;K_a2 is 1 $\times$ 10^-12)

Multiple Choice

Calculate the pH of a 0.04 M solution of ascorbic acid (K_a1 = 7.9 $\times$ 10^-5;K_a2 is 1.6 $\times$ 10^-12) .

A) 11.2
B) 2.8
C) 5.5
D) 8.5
E) 11.8