Unit 8 Acids and Bases

8.10 Buffer Capacity

Buffer capacity: represents the amount of H+ or OH- the buffer can absorb without a significant change in pH The buffer capacity is determined by the [A-] & [HA] (molarity)           ○ More moles = greater capacity           ○ Less moles = less capacity bcuz there...

8.9 Henderson-Hasselbalch Equation

○ Is only used to determine the pH of a buffer system                ○ Can be molarity, moles or mmols of A- & HA The pH of a buffered solution is determined by the ratio of [A-]/[HA]                ○ What if the acid and conjugate base are equal in...

8.8 Properties of Buffers

What is a Buffer? A weak acid and its conjugate base together ○ Conjugate base usually present within a salt A weak base and its conjugate acid together The purpose of a buffer is to resist changes in pH when either H+ or OH- are added Write the Reaction of… Adding a...

8.7 pH and pKa

pH and pKa If you know the pH and pKa on an environment, you can know the ratio of [A-]/[HA]           ○ If the ratio of [A-]/[HA] is > 1 → [HA] < [A-] & pH > pKa,           ○ If the ratio of [A-]/[HA] is < 1 → [HA] > [A-] & pH < pKa...

8.6 Molecular Structure of Acids and Bases

Note: stronger acid/base = less stable X-H Acids For X-H acids, there are two factors for acid strength Bond Strength (between H and other atom): low = strong acid bcuz H can easily dissociate Compare bond dissociation energies 2. Bond Polarity (high → weak acid) The...

8.4 Acid-Base Reactions, Buffers, & Titrations

In acid-base titrations/reactions, are dealing with neutralization reactions (Use NmN Tables→ water is not a reactant)             ○ N: neutralization reaction             ○ M: mmols                                                                                     ...

8.3 Weak Acid and Base Equilibria

Acid Dissociation Constant For weak acids only:   (note [H+] is the same as [H3O+])             ○ Strong acids don't have Ka Larger Ka = stronger weak acid → will produce more H3O+ ions and thus a lower (more acidic) pH Weak Acids Any acid that is not one of the 6...