What is the pH of 0.010 M aqueous hypochlorous acid? (K_a of HOCl = 3.5 $\times$ 10^-8)

Question

Quizplus · Accepted Answer

The pH of an aqueous solution of a weak acid can be calculated using the equation: pH = pKa + log([A-]/[HA]), where pKa is the acid dissociation constant, [A-] is the concentration of the conjugate base, and [HA] is the concentration of the acid. For hypochlorous acid, the pKa is 7.53 (according to the given constant value), and the conjugate base is hypochlorite ion (ClO-). The acid dissociation reaction is: HOCl + H2O ⇌ H3O+ + ClO-. Therefore, [A-]/[HA] = [ClO-]/[HOCl] = 1/((K_a of HOCl)^-1), which is 28.57. Plugging in these values, we get: pH = 7.53 + log(28.57) = 4.73. Therefore, the correct answer is C.

What Is the PH of 0 ×\times× 10-8) A) 2

What Is the PH of 0 $\times$ 10^-8)
A) 2