Calculate the pH of a 0.10 M solution of HOCl, K_a = 3.5 × 10^-8. A) 8.46 B) 4.23 C) 1.00 D) 3.73 E) 3.23

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Quizplus · Accepted Answer

The pH of a solution of HOCl can be calculated using the formula for weak acids: pH = 1/2(pKa - log[acid]). The pKa can be found by taking the negative logarithm of the acid dissociation constant (Ka), which is given as 3.5 × 10^-8. Thus, pKa = -log(3.5 × 10^-8) ≈ 7.46. Plugging into the formula: pH = 1/2(7.46 - log(0.10)) = 1/2(7.46 - (-1)) = 1/2(8.46) = 4.23.

Calculate the PH of a 0