Which of the following reactions would be classified as oxidation-reduction? Check all that apply. View Available Hint (s) Check all that apply. 2Na (s) + Cl2 (g) →2NaCl (s) Na (s) + CuCl (aq) →NaCl (aq) + Cu (s) NaCN (aq) + CuCl (aq) →NaCl (aq) + CuCN (s)

Answer:The 1st and 2nd reactions are the example of oxidation - reduction.

Explanation:

Oxidation is basically when a species loses electrons and reduction is basically when the species gains electrons.

A reaction is known as an oxidation - reduction reaction only if oxidation and reduction simultaneously occur in the reaction. It basically means if a species is getting oxidized in the reaction then the other species present in the system must be reduced in the reaction.

Oxidation-reduction reactions are also known as redox reactions.

In the 1st reaction the oxidation state of Na in reactant is 0 and in products is + 1 hence Na is oxidized and the oxidation state of chlorine is 0 in reactants and in products is - 1 so chlorine is reduced. Hence Na is oxidized and Cl is reduced so the reaction is a example of oxidation-reduction.

2Na (s) + Cl₂ (g) →2NaCl (s)

In the second reaction the oxidation state of Na in reactant is 0 and in products is + 1 hence Na is oxidized and the oxidation state of Cu is + 1 in reactant and 0 in products so Cu is reduced. Hence Na is oxidized and Cu is reduced so the reaction is an example of oxidation-reduction.

Na (s) + CuCl (aq) →NaCl (aq) + Cu (s)

In the third reaction the oxidation state of Na changes from + 1 to + 1 and that of Cu also changes from + 1 to + 1. So there is no change in oxidation state of the species present in reactants and products. Hence this reaction is not an example of oxidation and reduction.