| A | B |
|---|
| Democritus | ancient atomic concept |
| Aristotle | rejected atomic concept in ancient times |
| Joseph Priestly | his "improved air" experiments led to the discovery of oxygen and changed the notion of elements |
| Antoine Lavoisier | Law of Conservation of Mass during chemical changes |
| Robert Boyle | "The Sceptical Chemist" |
| Joseph Proust | Law of Definite Proportions |
| John Dalton | Law of Multiple Proportions, modern atomic concept |
| Joseph Gay-Lussac | Investigated gases and discovered that if mass and volume are held constant, pressure increases as temperature increases |
| Amedeo Avogadro | His investigations of gases led to the mole concept |
| Michael Faraday | Self-taught inventor of electric motor and electric generator, coined words electrolyte and non-electrolyte |
| Frederich Wohler | First to successfully synthesize an organic compound in the lab |
| Adolph Kolbe | Developed methods of synthesizing organic compounds, broadening the field of organic chemistry |
