Which of the following best describes oxidation?

Oxidation is best described as the loss of electrons. This concept stems from the definitions used in redox (reduction-oxidation) reactions, where oxidation refers specifically to the process in which an atom, ion, or molecule loses electrons, leading to an increase in its oxidation state.

In these reactions, when something is oxidized, it gives away electrons to another species, which is being reduced (the gaining of electrons). Therefore, understanding oxidation as the loss of electrons is crucial for balancing redox equations and for grasping various pathways of chemical reactions, especially in inorganic chemistry, where transition metals frequently undergo oxidation and reduction.

The other options relating to protons do not accurately capture the essence of oxidation in the context of electron transfer. While protons (H⁺) can be involved in some oxidative processes, the core definition of oxidation fundamentally revolves around electron transfer rather than proton transfer. This distinction is key to mastering redox chemistry and understanding the behavior of different elements and compounds in various chemical environments.