Weak Acids and Bases – Calculate the pH of a weak acid (a general equation)
Weak Acids and Bases – Calculate the pH of a weak acid (a general equation) Home > Weak Acids and Bases – Calculate the pH of a weak acid (a general equation) Weak Acids and Bases – Calculate the pH of a weak acid (a general equation) The weak acid (base) general equation Most acids known are weak while there are no more than twenty strong acids. The reactions of weak acids and bases with water do not go to completion. So to calculate the pH of their solutions ( pH of a weak acid or pH of a weak base ) the acid (or base) dissociation constants are used, k a and k b respectively, and the laws of chemical equilibrium. Let us now find a general equation for the pH of a weak acid HA (or for [H + ]). This is the mathematical approach. Mathematical Approach: There are two equilibria present: i) the dissociation