8.7 pH & pKa & 8.8 Properties of Buffer & 8.9 Henderson - Hasselbalch Equation

8.10 Buffer Capacity

Which one is the best indicator for the titration?

It always needs to be in the range of the equivalence point.

In this case it’s strong acid +strong base = equi. p.t. pH =7

Methyl Red

In other cases it’s

weak acid + strong base = equi. p.t. above 7

weak base + strong acid = equi. p.t. below 7

Diff btw equivalence p.t. and end point of a titrant.

Acid and Base indicators

What’s in a buffer?

1. Weak acid or Weak base
2. It’s conj. salt

e.g. NH3 & NH4+

What’s a neutral solution?

created to from equimolar amounts of a strong acid and base that reaction a 1:1 ratio.

When water is added to a solution (not buffer), what happens? How it affect pH?

Dilution happens, where the H ions will decrease (pH - potential H) so, pH increase.

Relationship btw pH and pKa

What will happen if acid or base is added but in small amounts to a buffered solution?

Relationship btw concentration, pH and capacity

Increasing the concentration of the buffer components (ratio constant) keeps pH of the buffer the same

But increases the capacity of the buffer to neutralize added acid or base

When a buffer has more conj.acid than base

Greater Buffer capacity for added base than added acid

When a buffer has more conj.base than acid

Greater buffer capacity for added acid than added base