60 years ago
US chemist Gilbert Newton Lewis died. His theory of the electron pair advanced understanding of the covalent bond and extended the concept of acids and bases.
90 years ago
Christian Boehmer Anfinsen was born in Pennsylvania, US. He shared the 1972 Nobel prize for chemistry with Stanford Moore and William Stein for research into the shape and primary structure of ribonuclease.
95 years ago
Jacobus Henricus van't Hoff died. Born in Rotterdam, the Netherlands, van't Hoff was the first recipient of the Nobel prize for chemistry. He was awarded the prize in 1901 for his work on chemical dynamics and osmotic pressure.
125 years ago
Hermann Staudinger was born in Germany. He showed that polymers consist of long chains, for which he won the 1953 Nobel prize for chemistry. His work has had great importance for the plastics industry.
130 years ago
French chemist Antoine-Jérôme Balard died. Known for his discovery of the element bromine in 1826, he also discovered oxamic acid and tutored Louis Pasteur.
195 years ago
Robert Wilhelm Bunsen was born in Germany. He invented the Bunsen burner, a well-known device for flame tests of metals.