Acids and Bases
Eleven topics on protons in solution. The pH of strong and weak acids and bases, how titration curves read, what molecular structure says about acid strength, comparing pH to pKa, and everything about buffers — their properties, the Henderson-Hasselbalch equation, capacity, and how pH drives solubility.
Topics
Equations For every problem in this unit
pH and pOH
pH = −log[H+]; pOH = −log[OH−]; pH + pOH = 14 (25°C)
Water
Kw = [H+][OH−] = 1.0 × 10−14 at 25°C
Strong acids/bases
dissociate completely (count the H+ or OH− per formula unit)
Weak acids/bases
partially ionize; larger Ka (or Kb) = stronger
Structure
binary: weaker/longer H–X bond; oxyacid: more O and more electronegative center
Conjugates
a stronger acid has a weaker conjugate base
Buffer
a weak acid and its conjugate base, or a weak base and its conjugate acid
Henderson-Hasselbalch
pH = pKa + log([A−]/[HA])
Capacity
more concentrated buffer holds pH longer; finite
Unit 1 tools
Challenge bank
60 open-ended problems.
Read the question, work it out, then flip the card to compare your reasoning to the worked solution. Mark each card so you can return to the ones that still bite.
Question
Tap card to reveal explanation
Worked solution
Tap card to return to question
Nothing here yet.
Switch to All, work through some cards, and tag them as Got it or Revisit.
Cumulative assessment
Test the unit.
Twenty mixed items pulled from across all 11 topics. Identifies which misconceptions still bite when you cannot see which topic the question came from.
20questions
11topics
19codes covered