Buffers, Titrations, and Solubility Summary

Flashcards summarizing key concepts related to buffers, titrations, and solubility.

Common Ion Effect

Shifts the equilibrium and decreases the solubility of a solid.

Ways to make a buffer

Mix a weak acid/base and salt of its conjugate base/acid OR Add a strong acid to partially neutralize a weak base, or add a strong base to partially neutralize a weak acid (strong part must be in lower concentration than weak).

Solubility

The ability of a substance to dissolve in a solvent to form a solution. Strong acids and bases are not affected by pH changes. If the substance has an anion from a weak acid (weak base), it is more soluble in acidic solution.

Ksp = Q

Saturated solution.

Ksp > Q

More solid can dissolve.

Ksp < Q

Precipitate forms.

Buffer Capacity

Buffer will work in a pH range that is ± 1 from the pKa.

Henderson-Hasselbalch Equation

Can only be used with buffers.

Buffers

Resist a change in pH when a strong acid/base is added with a combination of weak acid-base conjugate pairs; better at higher concentrations of the conjugate pair; strong acid reacts with the base part; strong base reacts with the acid part.

Equivalence Point (strong acid with strong base)

pH = 7

Buffer Region

pH = pKa