Redox and Voltaic Cell

Oxidation-Reduction Reaction

an electron transfer reaction

Oxidation-Reduction Reaction

coupled reaction

Oxidation-Reduction Reaction

no oxidation if there is no reduction ▪ no reduction if there is no oxidation

LEORA

Loss of Electron Oxidation Reducing Agent

GEROA

Gain of Electron Reduction Oxidizing Agent

Electrochemical Cells

devices that make use of the inter-conversion of electrical and chemical energy

Galvanic/Voltaic Cells

generate electricity from spontaneous reactions

Galvanic/Voltaic Cells

chemical energy to electrical energy

Electrolytic Cells

make use of electricity or electric current for certain chemical reactions to occur

Electrolytic Cells

electrical energy to chemical energy

Oxidation

occurs at the anode (negative electrode)

Reduction

occurs at the cathode (positive electrode)

Electrons

move from anode to cathode passing through the external wire

Electromotive Force (emf)

cell voltage or cell potential (E)

Anolyte

electrolyte solution where anode is immersed

Catholyte

electrolyte solution where cathode is immersed

Internal Circuit

consists of electrolyte in the salt bridge to maintain electrical neutrality

Anions

must flow towards the anolyte to neutralize the charge of cation that accumulates after oxidation

Cations

flow towards the catholyte to neutralize the anion