For Weak Acid,HX,K_a = 6 $\times$ 10^-6

Multiple Choice

For weak acid,HX,K_a = 6.9 $\times$ 10^-6.Calculate the pH of a 0.13 M solution of HX.

A) 0.89
B) 3.02
C) 6.05
D) 10.98
E) none of these