Buffer Solutions (Higher Level Only) - IB Chemistry

Definition and Importance

• Buffers are solutions that resist changes in pH when small amounts of acid (H⁺ ions) or base (OH⁻ ions) are added.
• They are essential for maintaining pH stability in:
  • Chemical reactions
  • Biological systems (e.g., blood)
  • Industrial processes

Functionality

• Without a buffer, adding a small amount of acid or base to a solution would cause dramatic pH changes.
• Analogy: Buffers act like sponges, absorbing H⁺ or OH⁻ ions to prevent drastic pH changes.

Components of a Buffer

• Consists of two key components:
  1. A weak acid and its conjugate base (e.g., CH₃COOH/CH₃COO⁻).

Example Calculation

• Consider a buffer solution prepared with:
  • Acetic acid (CH₃COOH) and sodium acetate (CH₃COONa)
  • Concentrations: 0.1 M each
  • Acid dissociation constant (Ka) for acetic acid: 1.8 × 10⁻⁵

Practical Applications

• Buffers are critical in experiments requiring constant pH.
• Common examples include:
  • Blood, maintaining a pH around 7.4
  • Swimming pools to stabilize water pH

Study Tools and Resources

• Interactive lessons, videos, and flashcards are available for deeper understanding and practice.

Note: This summary provides an overview of buffers as discussed in higher level IB Chemistry. For more detailed explanations and examples, refer to specified study materials or resources.