Proton Donation

Proton donation refers to the process by which a chemical species (an acid) donates a proton (\( \mathrm{H}^+ \)) to another species (a base) during a chemical reaction. This concept is central to the Brønsted-Lowry theory of acids and bases, where a Brønsted-Lowry acid is defined as any species capable of donating a proton, and a Brønsted-Lowry base is any species capable of accepting a proton. It underlies many fundamental processes in chemistry and biology including enzyme catalysis, buffer systems in blood, cellular respiration, and energy production via ATP hydrolysis. The tendency for substances to donate protons is measured by their pKa value.