Application of redox and reaction
Redox is a contraction of the name for a chemical reduction–oxidation reaction. A reduction reaction always occurs with an oxidation reaction. Redox reactions include all chemical reactions in which atoms have their oxidation state changed; in general, redox reactions involve the transfer of electrons between chemical species.
The chemical species from which the electron is stripped is said to have been oxidized, while the chemical species to which the electron is added is said to have been reduced. Oxygen is not necessarily included in such reactions as other chemical species can serve the same function.
Applications of Redox Reactions
Reduction is defined as the gain of electrons and oxidation is defined as loss of electrons. In other words, oxidation is loss whereas reduction is gain. The reaction which consists of both oxidation and reduction is termed as redox reaction. These redox reactions find numerous applications in real life.
Combustion is a type of oxidation-reduction reaction and hence it is a redox reaction. An explosion is a fast form of combustion and hence explosion can be treated as a redox reaction. Even the space shuttle uses redox reactions.
The combination of ammonium perchlorate and powdered aluminium inside the rocket boosters gives rise to oxidation-reduction reaction. Electrochemistry also finds its application with redox reactions. The study of relationship between chemical and electrical energy is defined as electrochemistry. The battery used for generating DC current uses redox reaction (oxidation-reduction) to produce electrical energy .
Example
Assigning Oxidation States
Determine the Oxidation States of each element in the following reactions:
a. Fe(s)+O2(g)→Fe2O3(g)Fe(s)+O2(g)→Fe2O3(g)
b. Fe2+Fe2+
c. Ag(s)+H2S→Ag2S(g)+H2(g)Ag(s)+H2S→Ag2S(g)+H2(g)
SOLUTIONS
A. Fe and O2 are free elements; therefore, they each have an OS of 0 according to Rule #1. The product has a total OS equal to 0, and following Rule #6, O has an OS of -2, which means Fe has an OS of +3.
B. The OS of Fe corresponds to its charge; therefore, the OS is +2.
C. Ag has an OS of 0, H has an OS of +1 according to Rule #5, S has an OS of -2 according to Rule #7, and hence Ag in Ag2S has an OS of +1.