Electrochemistry Cheat Sheet

Key Definitions

• Electrochemistry: Study of chemical processes that cause electrons to move.

• Oxidation: Loss of electrons; increase in oxidation state. ✅

• Reduction: Gain of electrons; decrease in oxidation state. ✅

• Redox Reaction: A reaction involving both oxidation and reduction. ✅

• Electrode: Conductor through which electricity enters or leaves an electrochemical cell. ✅

Important Concepts

Galvanic Cells

• Convert chemical energy into electrical energy.

• Consist of two half-cells: anode (oxidation) and cathode (reduction). ✅

Electrolytic Cells

• Use electrical energy to drive non-spontaneous reactions. ✅

• Commonly used in electroplating and electrolysis. ✅

Nernst Equation

• Relates cell potential to concentration of reactants/products:

• E°_cell: Standard cell potential ✅

• R: Universal gas constant (8.314 J/mol·K) ✅

• T: Temperature in Kelvin ✅

• n: Number of moles of electrons exchanged ✅

• F: Faraday's constant (96485 C/mol) ✅

• Q: Reaction quotient ✅

Key Formulas

• Cell Potential: E_cell = E°_cell - (RT/nF) * ln(Q) ✅

• Faraday's Law: Q = nF

• Q: Charge (Coulombs) ✅

• n: Moles of electrons transferred ✅

Common Mistakes to Avoid

Common Mistake: Confusing oxidation and reduction; remember OIL RIG (Oxidation Is Loss, Reduction Is Gain).

Memory Tricks

Tip: "LEO the lion says GER" — Loss of Electrons is Oxidation; Gain of Electrons is Reduction.

Key Diagrams

Galvanic Cell:
Anode (-)  |  Cathode (+)
   |            |
   |            |
  Zn |         Cu
  |  |         |
  |  |         |
  |  |         |
  |__|_________|

Electrolytic Cell:
Power Source (+) 
   |            |
   |            |
   |            |
  Anode (+)    Cathode (-)
   |            |
   |            |
  Metal Ions   Metal
  Solution     Coating