Svante Arrhenius [local] developed the notion that salts, acids, and bases will dissociate in water. Bronsted [local] worked on developing the idea that an acid reacts with its solvent to form hydronium ions. Sorensen [local] developed the pH model which originally was based on the H⁺ concentration.

The history of chemistry is more than just people who made noteworthy progress. It is also about processes, procedures, and impact on society. Soap [local] has an interesting history.