http://www.ck12.org Chapter 22. Oxidation Reduction Reactions
CHAPTER
(^22) Oxidation Reduction
Reactions
Chapter Outline
22.1 Nature of Oxidation and Reduction
22.2 OXIDATIONNUMBERS
22.3 BALANCINGREDOXEQUATIONS
22.4 REFERENCES
Have you ever seen someone breathe into a device like this? This person is breathing into a breathalyzer, a device
used to detect the presence of ethanol (an alcohol) in a person’s breath. One version of the breathalyzer works by
measuring the color change of a solution of the dichromate ion. In the presence of ethanol, the solution changes
from orange to green as the dichromate ion is converted to a chromium(III) ion. The extent of the color change is
then related to actual blood-alcohol content. The device is very accurate, because the chemical reaction on which
the device is based is very predictable. This is an example of an oxidation-reduction reaction.
Courtesy o f Senior Airman Natasha Stannard,U S Air Force.commons.wikimedia.org/wiki/File:Breathalyzer_study.j pg.Public Domain.