CM011 Study Guide - Quiz Guide: Standard Hydrogen Electrode, Electrochemical Cell, Electrolytic Cell
Document Summary
Electrochemical cells: an electrochemical cell is a system that converts chemical energy into electrical energy, electrochemical cells are divided into two types: galvanic cells and electrolytic cells. In a galvanic cell, the chemical reaction is spontaneous, and electrical energy is produced. In an electrolytic cell, an external source of electrical energy is used to drive a non-spontaneous chemical reaction. Oxidation-reduction (redox) reactions: oxidation: m m^n+ + ne^, reduction: n^n+ + ne^- n, redox reaction: m + n^n+ m^n+ + n. Electrochemical cells: standard cell notation: anode | anode solution || cathode solution | cathode, cell potential (ecell) = ered,cathode - ered,anode, free energy change ( g) = -nfecell, faraday"s constant (f) = 96,485 c/mol. Standard electrode potentials: standard hydrogen electrode (she): 2h^+ (aq) + 2e^- h2 (g) e = 0 v, standard reduction potential (e ) = - g /nf. Nernst equation: nernst equation: ecell = e cell - (rt/nf) ln q, equilibrium constant (k) = e^(ne cell/rt)
