CHE-1102 Lecture Notes - Lecture 7: Gastric Acid, Equilibrium Constant, Chief Operating Officer
Document Summary
Chapter 16 - acid-base equilibrium in aqueous solutions. Self-ionization: when a substance reacts with itself to form ions. In pure water, a few molecules act as bases and a few act as acids. Kw is called the ion-product constant for water. Kw = [h+][oh-] = 1. 00 x 10-14 (at 25 c) When [h+] = [oh-] solution is neutral. When [h+] > [oh-] solution is acidic. When [h=] < [oh-] solution is basic. In a sample of blood at 25 c, [h+] = 4. 6 x 10-8m find [oh-] and determine if the solution is acidic, basic, or neutral. Kw = [h+][oh-] = 1. 00 x 10-14. [oh-] = kw / [h+] = 1. 0 x 10-14 / 4. 6 x 10-8 = 2. 2 x 10. [oh-] > [h+] so solution is basic. Kw expression is valid for all aqueous solutions (acidic, basic, or neutral) at 25 c. 1ph unit has a 10 order of magnitude increase/decrease. When ph = 7 solution is neutral.