Unit Twelve Acids and Bases

Buffers Any solution that resists a change in pH Contains a weak acid and its conjugate base Buffers are used to maintain nearly constant pH in commercial and laboratory products The choice of buffer is determined by the final desired pH of the solution being prepared A buffer consisting of a weak acid (HB) and its conjugate base (B-) can react with a strong base (OH_) or a strong acid (H+)

Brønsted-Lowry System Conjugate acid-base pairs – two substances related to each other by the transfer of a proton Acid = proton donor Base = proton acceptor Conjugate Base = what remains after an acid has donated its H+ Conjugate Acid = what remains when a base has accepted a H+

A B CA CB A B CA CB B A CB CA A B CA CB A B CB CA

Retests until Tuesday Monday – Computer Lab Tuesday and Wednesday – Titration Lab Thursday – Extra Credit Lab Friday – Test (If gone need to be completed before you leave)