Answer:
pH = 1.98
Explanation:
Given a general acid dissociation:
HA + H₂O ⇆ H₃O⁺ + A⁻
The pH is -log[ H₃O⁺ ]
Therefore we need to determine [ H₃O⁺ ] to answer this question, and we should use the data of % dissociation of the acid.
Percent dissociation is
% dissociation = [ H₃O⁺ ] / [ HA ]₀ x 100
where [ HA ]₀ is the original acid concentration, so we can calculate [ H₃O⁺ ] , and then the pH.
12 = [ H₃O⁺ ] /0.089 M ⇒ [ H₃O⁺ ] = (12 x 0.089 /100) M
= 1.07 x 10⁻² M
and pH = - log ( 1.07 x 10⁻² ) = 1.98
