Answer:
Redox reactions
Step-by-step explanation:
Redox (Reduction-Oxidation) reactions are reactions which involves the transfer of electrons. Here, one specie loses electrons while the other gains the electrons. The loss and gain of electrons makes one atom reduced while the other becomes oxidized. Transfer of electrons from one specie to another would eventually lead to a change in oxidation number of the reactants as they proceed to form products.
In non-redox reactions, there is no loss or gain of electrons and no change in oxidation number. An example is neutralization reaction.