Core
Reactions: Redox
Slide 20 of 42
Oxidation States and Redox reactions
The origination of this type
of reaction was from reactions of oxygen with other elements.
The term oxidation when first
used was simply to denote the (chemical) addition of oxygen to another
substance.
But, when oxygen is added to
another element, and if that element is a metal, then
exchange of electrons take place.
So, the definition of
oxidation was expanded to include reactions involving the loss
of electrons, which is a more inclusive term.
But, when exchange of
electrons are presumed to take place, the oxidation state
changes as well.
What about those reactions
that don’t involve electrons exchanges but are accompanied by
changes in oxidation states?
There are a whole class of
reactions between elements (namely non-metals) no exchange
of electrons are involved but is accompanied by changes in oxidation
state.
It turned out that defining
oxidation and reduction (it’s twin process) in terms of
changes in oxidation state was an even more of an inclusive term.