Question

Study the reaction.

Answer 1

Answer: If the oxidation number of copper changes from 0 to +2 then yes this is a redox reaction as copper lost 2 electrons and was oxidized.

Explanation:

When an element or atoms loses an electron then it acquires a positive charge.

This charge on an atom represents its oxidation state.

For example, $2AgNO_{3}(aq) + Cu(s) \rightarrow Cu(NO_{3})_{2}(aq) + 2Ag(s)$

Here, oxidation number of copper changes from 0 to +2.

A redox reaction in which electrons are removed from an atom or a reaction where an increase in oxidation number of an atom takes place is called oxidation-half reaction. The atom itself gets oxidized.

This means that here copper lost 2 electrons and was oxidized.

Thus, we can conclude that if the oxidation number of copper changes from 0 to +2 then yes this is a redox reaction as copper lost 2 electrons and was oxidized.