University College - Chemistry Chem 112A Lecture 28: Laclanche Cell vs. Alkaline Cell
29 Mar 2017
School
Department
Professor
Document Summary
E is not additive, must be calculated from g . This is because e is an intensive property (independent of reaction events, only dependent on the process) i. e. the voltage is the same regardless of how many moles of electrons are transferred. G is extensive, it does depend on the number of electrons. Allows the calculation of potential after the cell has been producing current for some time (i. e. as [ ] changes) E1/2 cell = e 1/2 cell rt/nef*ln([ions in solutions]/[ ] ) Equilibrium constants from electrochemistry: pb2+ +2e- -> pb (s): e red = -0. 1263 v, pbso4 (s) + 2e- -> pb (s) + so4. Calculate ksp for pbso4 at 298k: pbso4 -> zn2+ + 2e- e red =-0. 76v.
