Why this chapter matters
This unit ties together energy, charge flow, and chemical change, completing the predictive framework for AP Chemistry.
What you will learn
- Interpret DeltaS and DeltaG to evaluate thermodynamic favorability.
- Use DeltaG = DeltaH - TDeltaS qualitatively and quantitatively in context.
- Analyze galvanic and electrolytic cells using half-reactions and standard cell potential.
Lessons in this chapter
- Entropy and spontaneityUse particle distribution and energy dispersal ideas to reason about DeltaS.
- Free energy relationshipsLink DeltaG sign to spontaneous direction under stated conditions.
- Galvanic and electrolytic cellsIdentify anode/cathode roles and electron-flow direction.
- Standard reduction potentialsCompute Ecell and infer whether a redox process is thermodynamically favorable.
Study task
For a given redox pair set, write balanced half-reactions, calculate standard Ecell from tabulated reduction potentials, and state whether the cell reaction is spontaneous under standard conditions.
Chapter checkpoint
If standard Ecell = +1.10 V for a galvanic cell, what can you conclude about spontaneity and standard DeltaG?
A positive standard Ecell means the cell reaction is spontaneous as written under standard conditions, and standard DeltaG is negative.