Acidez e Basicidade em Soluções

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Chapter 16 Acids and Bases 319 (b) Given: = 1. X 10⁻⁷ M Find: pH and pOH Conceptual Plan: pH pOH Solution: pH = 10⁻⁷) = 7.00 pH = 7, so the solution is neutral. Check: The units (none and none) are correct. When [H⁺] = 1 X 10⁻⁷ M the pH = 7 = pOH. (c) Given: [H₃O⁺] = 2.2 X 10⁻⁶ M Find: pH and pOH Conceptual Plan: [H₃O⁺] pH pOH Solution: pH = X = 5.66 pH 7. 16.51 pH = Kw = 1.0 10⁻¹⁴ = [H₃O⁺] [OH⁻] pH Acidic or Basic 1.4 X 10⁻¹¹ 3.15 acidic 2.7 X 10⁻⁶ 8.43 basic 11.1 basic 6.3 X 10⁻⁴ 1.6 X 10⁻¹¹ 3.20 acidic Check: When pH 10⁻⁷ M and 7, [H⁺] 10⁻⁷ M. 16.53 Given: Kw = 2.4 10⁻¹⁴ at Find: [H₃O⁺], pH Conceptual Plan: Kw [H₃O⁺] pH Solution: + H₃O⁺(aq) + Kw = X pH = -log[H₃O⁺] = 10⁻⁷) = 6.82 Check: The value of increased, indicating more products formed; so the increases and the pH decreases from the values at 25 °C. 16.55 (a) Given: = Find: pH Conceptual Plan: [H₃O⁺] pH Solution: pH = -log(0.044) = 1.357 = 1.36 (b) Given: [H₃O⁺] = 0.045 M Find: pH Conceptual Plan: [H₃O⁺] pH Solution: pH = -log(0.045) = 1.347 = 1.35 Copyright © 2017 Pearson Education, Inc.