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Difference between Ka and pKa.
Ka: Acid dissociation constant, measures acid strength (higher = stronger). pKa: -log(Ka), also measures acid strength (lower = stronger).
Difference between a strong acid and a weak acid in the context of buffers.
Strong Acid: Completely dissociates in solution, not suitable for buffers. Weak Acid: Partially dissociates, forms a buffer with its conjugate base.
Difference between using molarity and moles in the Henderson-Hasselbalch equation.
Molarity: Can be used if the volumes of the acid and conjugate base solutions are the same, so the volume cancels out in the ratio. Moles: Can always be used, regardless of volume, as the ratio is what matters.
Difference between equivalence point and half-equivalence point in a titration.
Equivalence Point: Moles of acid = moles of base. Half-Equivalence Point: Moles of acid = moles of conjugate base, pH = pKa.
Difference between acid and conjugate base.
Acid: Donates a proton (H+). Conjugate Base: Accepts a proton (H+).
Define a buffer solution.
A solution that resists changes in pH, consisting of a weak acid and its conjugate base (or a weak base and its conjugate acid).
Define pH.
A measure of acidity, calculated as -log[H+].
Define pKa.
-log(Ka), which indicates the acid's strength. A lower pKa means a stronger acid.
Define Ka.
The acid dissociation constant, a measure of the strength of an acid in solution.
What is the conjugate base?
The species formed when an acid donates a proton (H+).
Steps to find pH of a buffer (directly stated).
- Calculate pKa. 2. Apply the Henderson-Hasselbalch equation: pH = pKa + log([A-]/[HA]).
Steps to find pH during a titration using the Henderson-Hasselbalch equation.
- Write the net ionic equation. 2. Use stoichiometry to determine the amounts of acid and conjugate base after the reaction. 3. Apply the Henderson-Hasselbalch equation.
How to calculate pKa from Ka?
pKa = -log(Ka)
How to determine the concentrations of acid and conjugate base after the addition of a base in a titration?
Use stoichiometry based on the balanced net ionic equation to determine the remaining moles of acid and the moles of conjugate base formed.
Steps to determine pH using ICE table.
- Set up an ICE (Initial, Change, Equilibrium) table. 2. Write the Ka expression. 3. Solve for [H+]. 4. Calculate pH = -log[H+].