Page 3 - Pharmaceutical Analytical Chemistry II - Pharm D- 02-06-07102

OXIDATION REDUCTION REACTIONS
AND

INTRODUCTION TO ELECTROCHEMISTRY

OXIDATION-REDUCTION REACTION "REDOX REACTION"

It is the reaction in which electrons are transferred

OXIDATION Loss of electron(s) by a species
and

increase in oxidation number

Fe2+ ─ e– Fe3+ "Oxidation half-reaction"

REDUCTION Gain of electron(s) by a species
and

decrease in oxidation number

Ce4+ + e– Ce3+ "Reduction half-reaction"

OXIDIZING AGENT Electron acceptor; the species is reduced
REDUCING AGENT
REDOX COUPLE Ce4+
Electron donor; the species is oxidized

Fe2+
The oxidized and reduced forms of a substance,
Fe3+/Fe2+
MnO4─/ Mn2+

LEO goes GER
Loss of Electrons is Oxidation
Gain of Electrons is Reduction

ELECTRONS are neither created nor destroyed during a REDOX
REACTION, they are transferred from the species being oxidized
to that being reduced

Electron transfer = Charge transfer = Electrons flow → "CURRENT" rate at

which electrons flow (charge passed per unit time)--------- Electrical Energy

ELECTROCHEMISTRY

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