Electrochemistry and Redox Equilibria

Electrochemistry and Redox Equilibria

1. Application of Redox Equilibria

   • Oxidation Number
   • Redox
   • Half-Equation
   • Changes in Oxidation Number to Reaction Stoichiometry
   • Standard Electrode Potential
     • All [X] at 1.0 mol/dm3
     • All gases at a pressure of 1.0 atm
     • System is at a stated temperature, e.g. 298 K (25 C)
   • Standard Hydrogen Electrode
     • Pt Foil
     • 1 mol/dm3 of H+ (i.e. an acid)
     • H2 gas is bubbled through at a pressure of 1.0 atm.
     • H2(g) ↔ 2H+(aq) + 2e-
   • Calculate Ecell from standard electrode potential values and use them to predict thermodynamic feasibilty and extent of reactions.
   • Ecell is directly proportional to the ∆Stotal and lnK
   • Predictions using Ecell may not be borne out in practice due to kinetic effects and non-standard conditions
   • Redox Titrations

2. Transition Metals and their Chemistry