Chemistry 1027A/B Chapter Notes - Chapter 1.4: Buffer Solution, Equivalence Point, Conjugate Acid

• School: Western University
• Department: Chemistry
• Course: Chemistry 1027A/B
• Professor: Felix Lee

Document Summary

Buffers solutions capable of resisting ph changes: the acid and base in the buffer solution must not react with each other, the weak species it"s conj. Partner must be both present in significant amounts. Buffers work best with a 1:1 ratio of weak species to it"s conjugate. Equivalence point of a titration is reached when stoichiometric amounts of acid and base are present in the solution (same # moles of acid and base) Case 1: strong acid + strong base ph is 7 (neutral) Case 2: weak acid + strong base ph is > 7 (basic) Case 3: strong acid + weak base ph is < 7 (acidic) At the equivalence point, the only species present is the conjugate, which will then react with water. This reaction is ultimately responsible for the ph of the solution at the equivalence point. Acid-base indicators are used to detect the equivalence point in a titration.