Chad provides a comprehensive lesson on buffers and how to do buffer calculations. A buffer is a solution that resists changes in pH and is composed of a weak acid and its conjugate base. Chad discusses at length buffer solution preparation and the related buffer solution preparation calculations. He demonstrates that a buffer can be prepared with the proper ratio of any of the following three mixtures: weak acid / conjugate base, weak acid / strong base, or weak base / strong acid. A weak acid and its conjugate base should be mixed in approximately a 1:1 ratio. A weak acid and strong base should be mixed in approximately a 2:1 ratio. And a weak base and strong acid should be mixed in approximately a 2:1 ratio also. It is also shown that the buffer range is equal to pKa +/- 1, and that polyprotic acids therefore have multiple buffer ranges possible. pH Calculations with buffers are also demonstrated using the Henderson-Hasselbalch equation. Chad derives the Henderson-Hasselbalch equation from the Ka expression and then uses it to show how to calculate the pH of a buffer solution. Finally, he also shows how to calculate the pH change of a buffer following the addition of strong acid or strong base. I've embedded this playlist as a course on my website with all the lessons organized by chapter in a collapsible menu and much of the content from the study guide included on the page. Check this lesson out at If you want all my study guides, quizzes, final exam reviews, and practice exams, check out my General Chemistry Master Course at 00:00 Lesson Introduction 00:26 What is a Buffer? 07:12 pKa and Buffer Range 14:47 Buffer Solution Preparation 21:34 Henderson-Hasselbalch Equation Derivation 26:37 How to Calculate the pH of a Buffer Solution 31:03 How to Calculate the Change in pH of a Buffer upon Addition of Strong Acid or Base