What is the hydroxide ion concentration of a lye solution that has a pH of 9.20? A)6.3 × 10^-10 mol L^-1 B)1.6 × 10^-5 mol L^-1 C)4.8 mol L^-1 D)9.2 mol L^-1

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Quizplus · Accepted Answer

The pH of a solution is defined as the negative logarithm of the hydrogen ion concentration (pH = -log[H+]). To find the hydroxide ion concentration, we can use the equation Kw = [H+][OH-], where Kw is the ion product constant for water (1.0 x 10^-14 at 25°C). Rearranging this equation, we get [OH-] = Kw/[H+]. At pH 9.20, the hydrogen ion concentration is 10^-9.20 = 6.31 x 10^-10. Substituting into the equation for [OH-], we get [OH-] = (1.0 x 10^-14)/(6.31 x 10^-10) = 1.59 x 10^-5 mol/L or 1.6 x 10^-5 mol/L (to two significant figures). Therefore, the correct answer is B.

What Is the Hydroxide Ion Concentration of a Lye Solution