Conant's investigations helped in the development of a more comprehensive understanding of the nature of acids and bases.  He investigated the properties of certain acids which were many times stronger than mineral acid solutions in water. Conant christened them " superacids "  and laid the foundation for the development of the Hammett acidity function .  These investigations used acetic acid as the solvent and demonstrated that sodium acetate behaves as a base under these conditions.   This observation is consistent with Brønsted–Lowry acid–base theory (published in 1923)  but cannot be explained under older Arrhenius theory approaches . Later work with George Wheland  and extended by William Kirk McEwen  looked at the properties of hydrocarbons as very weak acids, including acetophenone , phenylacetylene , fluorene and diphenylmethane . Conant can be considered alongside Brønsted , Lowry , Lewis , and Hammett as a developer of modern understanding of acids and bases.