Question

SO42- 2NO2 H2OH2SO3 2NO3- In the above redox reaction, using oxidation numbers to identify the element oxidized, the element reduced, the oxidizing agent and the reducing agent.

Answer 1

Answer :  In the redox reaction,

Nitrogen element is oxidized and sulfur element is reduced.

$NO_2$ act as reducing agent and $SO_4^{2-}$ act as an oxidizing agent.

Explanation :

Redox reaction or Oxidation-reduction reaction : It is defined as the reaction in which the oxidation and reduction reaction takes place simultaneously.

Oxidation reaction : It is defined as the reaction in which a substance looses its electrons. In this, oxidation state of an element increases. Or we can say that in oxidation, the loss of electrons takes place.

Reduction reaction : It is defined as the reaction in which a substance gains electrons. In this, oxidation state of an element decreases. Or we can say that in reduction, the gain of electrons takes place.

Reducing agent : It is defined as the agent which helps the other substance to reduce and itself gets oxidized. Thus, it will undergo oxidation reaction.

Oxidizing agent : It is defined as the agent which helps the other substance to oxidize and itself gets reduced. Thus, it will undergo reduction reaction.

The given chemical reaction is,

$SO_4^{2-}+2NO_2+H_2O\rightarrow H_2SO_3+2NO_3^-$

This reaction is a redox reaction in which nitrogen shows oxidation reaction because the oxidation state of 'N' changes from (+4) to (+5) and sulfur shows reduction reaction because the oxidation state of 'S' changes from (+6) to (+4).

In the redox reaction $NO_2$ act as reducing agent and $SO_4^{2-}$ act as an oxidizing agent.