Abstract for Lecture #21 - pH of (a)Weak Acid Solutions, (b) Bases, (c) Polyprotic Acids, and (d) Salts


Using the treatment for general equilibria given in chapter 6, we show how to analyze acid - base equilibria for weak acids in the case where the ionization of water can be neglected. Generally, this results in the need to solve a quadratic equation in proton concentration.

We give a similar treatment for the problem of finding the pH of a solution of a weak base. This too results in the need to solve a quadratic equation, but this time in terms of the the hydroxide concentration.

We show how to treat polyprotic acids in the case where the Kas are far apart and the ionization of water can be neglected. `

Finally, we show how to derive the pH of salt solutions.

To prepare for this lecture, please read sections 7.5 through 7.8 of Zumdahl.


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