Electrochemistry is the branch of chemistry that studies the relationship between electrical quantities and chemical reactions, particularly oxidation and reduction. Oxidation is the loss of electrons from a substance, whereas reduction refers to the gain of electrons. A substance with a strong electron affinity is called an oxidizing agent (oxidant), and a reducing agent (reductant) is a species that donates electrons. Oxidation and reduction processes are pivotal to electrochemical reactions, which can be further understood through half-reactions.

When electrons flow through an electric circuit, the measured current and cell voltage can reveal information about the type of reaction. During an electrochemical reaction, the current is proportional to the reaction rate, whereas the voltage is proportional to the free energy change for the reaction. According to Ohm's law, the current is inversely proportional to the resistance of the circuit and directly proportional to the applied potential. This means electrochemical experiments can determine the free energy change and reaction rates by varying potential or current. Electrochemical methods involve inexpensive instruments that provide an advantage over other analytical techniques.

From Chapter 10:

article

Now Playing

10.1 : Electrochemistry: Overview

Electrochemical Analyses and Redox Titration

350 Views

article

10.2 : Electrodes: Overview

Electrochemical Analyses and Redox Titration

217 Views

article

10.3 : Interfacial Electrochemical Methods: Overview

Electrochemical Analyses and Redox Titration

152 Views

article

10.4 : Potentiometry: Overview

Electrochemical Analyses and Redox Titration

280 Views

article

10.5 : Potentiometry: Types of Electrodes

Electrochemical Analyses and Redox Titration

282 Views

article

10.6 : Potentiometry: Membrane Electrodes

Electrochemical Analyses and Redox Titration

230 Views

article

10.7 : Redox Titration: Overview

Electrochemical Analyses and Redox Titration

175 Views

article

10.8 : Redox Titration: Iodimetry and Iodometry

Electrochemical Analyses and Redox Titration

376 Views

article

10.9 : Redox Titration: Other Oxidizing and Reducing Agents

Electrochemical Analyses and Redox Titration

109 Views

article

10.10 : Potentiometric Titration: Overview

Electrochemical Analyses and Redox Titration

239 Views

article

10.11 : End Point Prediction: Gran Plot

Electrochemical Analyses and Redox Titration

102 Views

article

10.12 : Electrogravimetric Analysis: Overview

Electrochemical Analyses and Redox Titration

102 Views

article

10.13 : Coulometry: Overview

Electrochemical Analyses and Redox Titration

102 Views

article

10.14 : Controlled-Potential Coulometry: Electrolytic Methods

Electrochemical Analyses and Redox Titration

78 Views

article

10.15 : Controlled-Current Coulometry: Overview

Electrochemical Analyses and Redox Titration

101 Views

See More

JoVE Logo

Privacy

Terms of Use

Policies

Research

Education

ABOUT JoVE

Copyright © 2025 MyJoVE Corporation. All rights reserved