Introduction to OXIDATION-REDUCTION REACTIONS in term of electrons (REDOX reactions)| Definition, Examples|

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Oxidation-Reduction Reactions
REDOX Reactions
Oxidation reduction reactions are also known as REDOX reactions. In oxidation reduction reactions electrons move between the atoms. In the figure below atom "A" giving electron,so in atom "A" oxidation is taking place and atom B is receiving that electron so in atom "B" reduction is taking place.As atom "A" is giving electron so its positive charge increases i.e its OXIDATION NUMBER is increasing and atom " B" is receiving electron so its positive charge decreases i.e its OXIDATION NUMBER is decreasing. Oxidation and reduction are the name of processes. Atom  "A" in which oxidation occurs get oxidized and the atom "B" in which reduction occurs get reduced.

REDOX-reactions-oxidation-reduction

So, we can define as
"Oxidation is loss of electrons and increase of oxidation number and reduction is gain of electrons and decrease in oxidation number."

Table is giving summary Of definition for REDOX REACTIONS

REDOX-REACTIONS-SUMMARY-TABLE

Term reduction is little bit confusing. Reduction means to decrease but reduction is is gain of electrons. So we can have a trick to memorize it.
OIL = oxidation is Loss
RIG=  reduction is gain.
It is Oxidation and reduction which occurs in for ionic compound formation.Lets take an example of sodium chloride(table salt)  to understand REDOX reactions.

Sodium Na and chlorine Cl combine to form sodium chloride NaCl. NaCl is an ionic compound made up of ions Na+ and Cl- .Na+ and Cl-  did not have always charges. They were neutral atoms before.

 How they become charged?
 Na is giving an electron so oxidation is taking place in Na. Cl is receiving electron so reduction is taking place in Cl.we can show this process in a chemical equation.


Above Chemical equation consist of two half reactions
Oxidation Half Reaction:
Oxidation-half-reaction

Reduction Half Reaction:
Reduction-half-reaction

It is very important to keep in mind oxidation and reduction both take place simultaneously. It is simple to understand, in given example Na is giving electron and that electron is receiving by Cl .Hence an ionic compound is forming.

Related video for REDOX REACTIONS


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