What mass of potassium hypochlorite must be added to 450. mL of water to give a solution with pH = 10.20? [K_a(HClO) = 4.0 * 10^-8] A) 20. g B) 0.032 g C) 4.1 g D) 2.4 g E) 9.1 g

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Quizplus · Accepted Answer

To find the mass of potassium hypochlorite (KClO) needed, first calculate the concentration of ClO⁻ using the pH and the K_a of HClO. The pH of 10.20 corresponds to a pOH of 3.80, giving an OH⁻ concentration of 1.58 x 10⁻⁴ M. Using the K_a and the relationship between K_w, K_a, and K_b, calculate the concentration of ClO⁻. Then, use the molarity and volume to find the moles of KClO needed, and convert this to mass using the molar mass of KClO. This calculation results in approximately 4.1 g.

What Mass of Potassium Hypochlorite Must Be Added to 450