What is the definition of oxidation in terms of electron transfer?

The definition of oxidation in terms of electron transfer specifically refers to the loss of electrons. When a substance is oxidized, it loses electrons, resulting in an increase in its oxidation state. This process is fundamental in various chemical reactions, particularly in redox (reduction-oxidation) reactions where the transfer of electrons between substances is crucial.

For example, in the reaction between hydrogen and oxygen to form water, hydrogen is oxidized as it loses electrons, while oxygen is reduced as it gains electrons. Understanding this concept is essential in fields such as chemistry and biology, where oxidation-reduction reactions play important roles in processes like cellular respiration and combustion.

The other options do not accurately describe oxidation. The gain of protons and the gain of neutrons do not relate to the electron transfer that defines oxidation. Similarly, the loss of protons does not pertain to the change in oxidation state based on electron movement. Thus, recognizing that oxidation involves specifically the loss of electrons is crucial for correctly understanding this fundamental chemical concept.