Question

Explain redox reaction on the basis of electron transfer. Give suitable examples.

Answer 1

Redox reaction-It is defined as a chemical reaction in which reduction and oxidation takes place simultaneously.

Redox reaction can be divided into two half reaction:

Oxidation half reaction- In this reaction, the reactant's oxidation state increases as the reactant loses electrons.

Reduction half reaction- In this reaction, reactant's oxidation state decreases as reactant gains electron.

Thus, in a redox reaction, transfer of electrons takes place as reactants gain or lose electrons to undergo reduction and oxidation simultaneously.

Reaction involved:

$CuO+H_2\to Cu+H_{2}O$

$Cu=+2H=0Cu=0H=+1$

$O=-2O=-2$

Corresponding half-cell reactions:

Oxidation half cell

$H_2\to 2H^{+}+2e^{-}$

Here $H_2$ is losing 2 electrons to get oxidised to $H^{+}$ions.

Reduction Half cell

$C{u}^{2^{+}}+2e^{-}\to Cu$

Here $C{u}^{2^{+}}$ is gaining 2 electrons to get reduced to $Cu$.

Thus, on combining both half-cell reactions, we get the net reation:

$CuO+H_2\to Cu+H_{2}O$

Where, $CuO$ is getting reduced to $Cu$ and $H_2$ is getting oxidised to $H_{2}O$.

Here, the oxidation and reduction process is taking place simultaneously, and electrons transfer is taking place,that's why this reaction is an example of redox reaction.