Question

What is Redox reaction?

Answer 1

REDOX REACTION : Those reactions are called redox reactions in which oxidation and reduction of same substance occurs simultaneously.

Oxidation : In oxidation, loss of electron occurs.

Reduction : In reduction, gain of electron occurs.

An example of a redox reaction is:

2 Fe2CO3 (s) + 3C (s) → 4 Fe (s) + 3 CO2 (g)
 In this reaction, it is clear that it is a redox reaction, because there electron transfer in the reaction.
 
Carbon is being oxidised as its oxidation number increases from 0 to +4.
Iron is being reduced because its oxidation number decreases from +3 to 0.

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Answer 2

Redox reaction :

In a chemical reaction when both oxidation and reduction takes place simultaneously then it is called Redox reaction.

Example :

$\bf CuO + H_{2} \: ➞ \: Cu + H_{2}O$

⠀ ⠀⠀ ⠀ ⠀⠀ ⠀

$\bf Here$

$\bf Substance \: oxidised : H_{2}$

$\bf Substance \: reduced : CuO$

$\bf Oxidising \: agent : CuO$

$\bf Reducing \: agent : H_{2}$