Hydrogen Peroxide Has Been Used as a Bleach to Change

Hydrogen peroxide has been used as a bleach to change hair color, as a disinfectant to treat wounds and as a rocket fuel. It is also a weak acid. Calculate the pH of a 0.018 M H₂O₂ solution. (H₂O₂: K_a = 2.2 x 10^-12)

A) 0.6
B) 6.7
C) 7.3
D) 11.7
E) 13.4