Titration and Buffers Buffers Buffers are substances that are able to absorb and release H+ ions keeping the pH in a solution constant. – EX: H 3 O + + HCO 3 -  H 2 CO 3 + OH -  H 2 O + HCO 3 - The amount of acid/base can be absorbed without changing the pH of a solution is called the buffer capacity.

Chemical indicator Is a weak acid or base that changes colors at a certain pH Each indicator has a specific pH range in which it dissociates to yield [H + ] or [OH - ] ions and change colors

Acid Base Titration The acid/base titration is a controlled neutralization reaction. The equivalence point (point of neutralization) is the point where the pH is = 7 and is the mid point in the titration curve. at the equivalence point the amount of [H 3 O + ] = [OH - ]

Categories of Acids - Binary Acids Contains hydrogen and one other ion Are strong acids – example - HCl, HBr, HI

Oxy Acids Contains hydrogen, oxygen, and one other element Can be both strong or weak acids – example - HNO 3, H 2 SO 4,H 3 PO 4

Carboxylic Acids Contain carbon and a carboxyl group (-COOH) Are organic acids most are classified as weak – example - HC 2 H 3 O 2

Categories of Bases Anions – Contain negatively charged monatomic or polyatomic ions – Can be either strong or weak example -CaO, Na 2 CO 3 Amines – Contain an amine group (NH 2 ) example - NH 3 (ammonia), CH 3 NH 2 (Methylamine)