Electrochemistry

Syllabus tag: KCSE | Chemistry | Form 4 | Topic 21 Electrochemistry

Lesson objectives

By the end of this topic, you should be able to:

• Define oxidation and reduction in terms of electrons and oxidation numbers.
• Identify oxidising and reducing agents in redox reactions.
• Describe the electrochemical series and electrochemical cells.
• Apply Faraday's laws and describe applications of electrolysis.

Summary

Oxidation is loss of electrons; reduction is gain — OIL RIG. The oxidising agent is the substance reduced, and the reducing agent is the substance oxidised. An electrochemical cell generates electricity from a redox reaction, and its e.m.f. is found from the electrode potentials. Faraday's laws relate mass deposited to quantity of electricity.