Respuesta :
Answer: The correct answer is Option a.
Explanation:
Oxidation-reduction reaction or redox reaction is defined as the reaction in which oxidation and reduction reactions occur simultaneously.
Oxidation reaction is defined as the reaction in which a substance looses its electrons. The oxidation state of the substance increases.
Reduction reaction is defined as the reaction in which a substance gains electrons. The oxidation state of the substance gets reduced.
For the given options:
Option A: [tex]Fe_2O_3+3CO\rightarrow 2Fe+3CO_2[/tex]
On reactant side:
Oxidation state of iron = +3
Oxidation state of carbon = +2
On product side:
Oxidation state of iron = 0
Oxidation state of carbon = +4
The oxidation state of iron reduces from +3 to 0, it is getting reduced. Thus, it is getting reduced and it undergoes reduction reaction. The oxidation state of carbon increases from +2 to +4. Thus, it is getting oxidized and it undergoes oxidation reaction.
Thus, it is considered as redox reaction.
Option B: [tex]CuSO_4+2NaOH\rightarrow Cu(OH)_2+Na_2SO_4[/tex]
The above reaction is double displacement reaction because here exchange of ions takes place.
Option C: [tex]2NaOH+H_2CO_3\rightarrow Na_2CO_3+2H_2O[/tex]
The above reaction is a neutralization reaction because an acid reacts with base to produce salt and water.
Option D: [tex]Pb(NO_3)2+Na_2SO_4\rightarrow 2NaNO_3+PbSO_4[/tex]
The above reaction is double displacement reaction because here exchange of ions takes place.
Hence, the correct answer is Option A.
