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Questions
What is the reaction called when oxidation and reduction take place simultaneously? Explain with one example.
What is called for the reaction which involves oxidation and reduction simultaneously? Explain with one example.
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Solution 1
The process in which oxidation and reduction occur simultaneously is called as redox reaction.
- Oxidation is the loss of electrons or an increase in oxidation state by a molecule, atom, or ion.
- Reduction is the gain of electrons or a decrease in oxidation state by a molecule, atom, or ion.
For example: If we add a stannous chloride solution to the yellow solution of ferric chloride then light green ferrous chloride solution and stannic chloride solution are produced.
Before the reaction, 3Cl atoms were attached to each iron atom. After the reaction, only two chlorine atoms are attached. That is one negative chlorine atom is released. Therefore, reduction of FeCl3 happened or this reactor on the other hand, before the reaction two chlorine atoms were attached with each atom of tin (stannum). Due to the above reaction, the number of chlorine attached to the tin atom increases to four. That is, oxidation of SnCl2 has taken place. Therefore, in this reaction oxidation of one substance and reduction of another substance take place simultaneously. This is called a redox reaction.
Solution 2
The reaction in which oxidation and reduction takes place simultaneously is called a redox reaction.
Example:
\[\ce{CuO + H2 -> Cu + H2O}\]
In this reaction, CuO loses oxygen to form Cu. This means that reduction of CuO takes place. H2 molecule takes up oxygen to form H2O. This means that oxidation of H2 takes place. Both the oxidation and reduction reactions always occur simultaneously.
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