A saturated aqueous solution of calcium hydroxide has a pH of 12.25. What is the [Ca²⁺] of such a solution? A) 0.018 B) 5.6 × 10^-13 C) 2.3 × 10^-5 D) 0.035 E) 8.9 × 10^-3

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Quizplus · Accepted Answer

The pH of 12.25 corresponds to a pOH of 1.75, giving [OH⁻] = 10^(-1.75) = 0.018 M. Since Ca(OH)₂ dissociates into one Ca²⁺ and two OH⁻ ions, [Ca²⁺] = 0.018 M / 2 = 0.009 M, which is approximately 8.9 × 10⁻³ M.

A Saturated Aqueous Solution of Calcium Hydroxide Has a PH