Lecture Notes: Acids and Bases

Introduction

• Acids and Bases Strength
  • Stomach acid = strong acid
  • Ammonia = weak base

Weak Acids and Bases

• Weak Acids
  • Example: Ethanoic acid
  • Partial ionization; equilibrium lies to the left
  • Conjugate base: Ethanolate ion
  • Poor proton donors
• Weak Bases
  • Example: Ammonia
  • Partial ionization in aqueous solution

Strong Acids and Bases

• Strong Acids
  • Example: Hydrobromic acid
  • Complete ionization; equilibrium lies to the right
  • Strong proton donors
• Strong Bases
  • Example: Sodium hydroxide
  • Fully dissociates into ions

Common Examples

• Strong Acids: Acid halides (except HCl), HNO₃, H₂SO₄
• Weak Acids: H₂CO₃, H₃PO₄
• Strong Bases: Group 1 hydroxides, soluble Group 2 hydroxides
• Weak Bases: Ammonia, methylamine

Concentration vs Strength

• Concentration
  • Measure of solute amount in solution
  • High concentration ≠ strong acid/base
• Strength
  • Degree of ionization

Properties of Strong vs Weak Acids/Bases

• Electrical Conductivity
  • Strong acids/bases have higher conductivity due to more ions
• Reaction Rate
  • Faster in solutions with more ions
• pH
  • Lower in strong acids; higher in strong bases

Acid-Base Reactions (Neutralization)

• Products: Salt and water
• Example: HCl + KOH → KCl + H₂O
• Exothermic
• Parent Acid/Base: Components of salt formed

Reactions with Metal Carbonates

• Produces salt, water, and CO₂ gas

Titration

• Process: Measure concentration of acid/base
• Equipment: Burette, pH meter, conical flask
• Equivalence Point
  • Neutralization point; moles of acid = moles of base
  • pH is 7 for strong acid-base titrations
• End Point
  • Indicator color change
• Data Collection
  • Repeat for reliable results (concordant)
  • Calculate concentration using titration data

Summary

• Strength vs Concentration
  • Strength: Degree of ionization
  • Concentration: Amount of solute
• Neutralization Reaction
  • Produces salt and water
  • Titration helps determine concentration of unknown solutions

These notes reflect the key points and main ideas covered in the lecture on acids and bases, focusing on their strengths, reactions, and titration process.