Redox Reactions And Electrochemistry

Front 1

Oxidation

Back 1

Loss of Electrons

Front 2

Reduction

Back 2

Gain of electrons.

Front 3

Oxidizing Agent

Back 3

Causes another atom to undergo oxidation, and is itself reduced.

Front 4

Reducing Agent

Back 4

Causes another atom to be reduced, and is itself Oxidized.

Front 5

Galvanic Cells

Back 5

Front 6

Galvanic Cells

Back 6

A redox reaction occurring in a galvanic cell has a negative Delta G and is therefore a spontaneous reaction. Galvanic Cell reactions supply energy and are used to do work. This energy can be harnessed by placing the oxidation-reduction half-reactions in separate containers called half-cells. The half-cells are then connected by an apparatus that allows for the flow of electrons.

Front 7

Electrolytic Cells

Back 7

Front 8

Electrolytic Cells

Back 8

A redox reaction occurring in an electrolytic cell has a positive delta G and is therefore non-spontaneous. In electrolysis, electrical energy is required to induce a reaction. The oxidation and reduction half-reactions are usually placed in one container.

Front 9

Reduction Potential

Back 9

Is defined as the tendency of a species to acquire electrons and be reduced. Standard reduction potential is measured under standard conditions: 25 Degrees Celsius, 1 M concentrations for each ion in the reaction, a partial pressure of 1 atm for each gas and metals in their pure state.

Front 10

Standard Reduction Potentials

Back 10

Used to calculate the standard EMF of a reaction, the difference in potential between two half-cells.

EMF = Ecathode - Eanode

Front 11

Gibbs Free Energy (Delta G)

Back 11

Is the thermodynamic criterion for determining the spontaneity of a reaction.

Delta G = -n*F*Ecell