- Joseph Black, born 1728, developed concept of latent heat; laid foundation for modern quantitative analysis.
- Humphry Davy performed first physiological experiment on nitrous oxide by inhaling it in 1799.
- Sidney G. Thomas, born 1850, solved problem of separating phosphorus from iron in Bessemer converter.
- Marie M. Daly, born 1921, first African-American woman to earn a Ph. D. in chemistry (Columbia University, 1948).
- Albert Hofmann accidentally discovered hallucinogenic effects of lysergic acid diethylamide (LSD) in 1943.
- Georges J. F. Köhler, born 1946, codiscovered technique for producing monoclonal antibodies; Nobel Prize in Medicine (1984).
- P-E. Lecog de Boisbaudran, born 1838, discovered gallium (Ga,31), dysprosium (Dy,66), and samarium (Sm,62).
- Samuel C. Hooker, born 1864, sugar chemist.
- Marston T. Bogart, born 1868, researcher on synthesis of quinazolines and thiazoles.
- W. Albert Noyes, Jr., born 1898, editor of Journal of the American Chemical Society (1950–1962).
- Quantum Chemical was incorporated as National Distillers Products Corp. in 1924.
- In 1776, Antoine L. Lavoisier admitted he and Joseph Priestley discovered the same facts about oxygen, but Lavoisier claimed the right to its discovery because he recognized it as an element. Priestley explained its formation in terms of phlogiston.
- Glenn T. Seaborg, born 1912; in 1940, codiscovered plutonium (Pu, 94); in 1944, codiscovered americium (Am, 95) and curium (Cm, 96); in 1949, codiscovered berkelium (Bk, 97); in 1950, codiscovered californium (Cf, 98); in 1952, codiscovered einsteinium (Es, 99) and fermium (Fm,100), in 1955, codiscovered mendelevium (Md, 101); in 1958, codiscovered nobelium (No, 102); in 1974, seaborgium (Sg, 106); Nobel Prize in Chemistry (1951).
- Monsanto Co. was incorporated in 1933.
- Champion International was incorporated in 1954.
- Jean-Baptiste Biot, born 1774, discovered optical activity.
- Percy W. Bridgman, born 1882, studied effect of pressure on substances; showed viscosity increases with high pressure; Nobel Prize in Physics (1946).
- Paul Karrer, born 1889, synthesized vitamin A (1931); in 1935, synthesized vitamin B2 (riboflavin); in 1938, synthesized vitamin E (tocopherol); Nobel Prize in Chemistry (1937).
- Pfizer incorporated in 1900.
- Nalco Chemical Co. incorporated as National Aluminate Corp. in 1928.
- First Earth Day, founded by Gaylord Nelson and organized by Denis Hayes, was celebrated in 1970.