In terms of aqueous chemistry, what is oxidation?

Oxidation in the context of aqueous chemistry refers specifically to the loss of electrons in a chemical reaction. This process is fundamental to redox (reduction-oxidation) reactions, where one species undergoes oxidation while another undergoes reduction.

During oxidation, when a substance loses electrons, its oxidation state increases. This change in oxidation state is an essential part of understanding how different species interact in an aqueous solution. For instance, if you have a metal that is oxidized, it typically means it is reacting with an oxidizing agent, losing electrons that may then be accepted by another reactant.

On the other hand, the other choices discuss different concepts that are not aligned with the definition of oxidation. Gaining protons and electrons are associated with reduction processes, while the formation of gases can occur in various reactions but does not directly define oxidation. Thus, the loss of electrons is what characterizes oxidation, making this option the correct interpretation of the term within the framework of aqueous chemistry.