Calculate the pH of a solution made by a mixture of the following acids: 0.40 M HC₂H₃O₂ (K_a = 1.8 × 10^-5), 0.10 M HOCl (K_a = 3.5 × 10^-8), and 0.20 M HCN (K_a = 6.2 × 10^-10). A) 2.57 B) 3.92 C) 4.95 D) 4.23 E) 3.49

Question

Quizplus · Accepted Answer

The pH of the solution is determined by the acid with the highest concentration and the largest Ka value, which is HC₂H₃O₂ (0.40 M, Ka = 1.8 × 10^-5). Using the formula pH = 1/2(pKa - log[C]), where pKa = -log(Ka), we find pH = 1/2(-log(1.8 × 10^-5) - log(0.40)) ≈ 2.57.

Calculate the PH of a Solution Made by a Mixture