Which chemical equation represents a redox reaction? a. mg(clo3)2 + 2hcl → mgcl2 + 2hclo3 b. co + h2o → h2 + co2 c. 2nh4no3 + cucl2 → 2nh4cl + cu(no3)2 d. na2so3 + febr2 → 2nabr + feso3

The correct answer is option B, that is, CO + H2O → H2 + CO2

The redox reactions are regarded as the chemical reactions in which one reactant goes through the process of reduction and one reactant goes through the process of oxidation. The reduction reactions are the reactions in which gain of electrons occurs, while oxidation reactions are the reactions in which loss of electrons occurs.  

From the mentioned options, only option B, that is, CO + H2O → H2 + CO2 is a kind of redox reaction. In this, the carbon is getting oxidized from +2 to +4 oxidation state, and hydrogen is getting reduced from +1 to 0 oxidation state. Hence, this reaction can be regarded as a redox reaction.  

The correct answer is

B.  CO + H2O → H2 + CO2