CHEM 105bL Chapter 16: Chapter 16 - Aqueous Ionic Equilibrium
Document Summary
A buffer resists ph change by neutralizing added acid or added base. A buffer contains significant amounts of weak acid and its conjugate base or significant amounts of weak base and its conjugate acid. The common ion effect occurs when a solution contains two substances that share a common ion; thus the initial concentration must be included in the initial amounts. The henderson-hasselbalch equation allows us to calculate the ph of a buffer solution from the initial concentrations of the buffer components: (cid:1868)=(cid:1868)(cid:3028)+log[(cid:3029)(cid:3028)(cid:3046)(cid:3032)] The equation is only valid if the change (x) is too small: 1) the initial concentrations of acids or bases are too dilute; 2) the equilibrium constant is very small. Calculate in two parts: 1) use stoichiometry to neutralize the equation; 2) use an ice table or. The capacity of a buffer is how much acid or base it can effectively neutralize.
