1. Coined the chemistry term elements.
2. Discovered arsenic and silver nitrate.
3. Proposed an early form of the scientific method and tinkered with gunpowder.
4. In 1615, he drew the first chemical equation.
5. He talked about atoms, molecules, and chemical reactions, marking the beginning of modern chemistry.
6. First to isolate carbon dioxide which he called fixed air.
7. He discovered hydrogen as a colorless, odorless gas that easily explodes.
8. He was the first to isolate oxygen which he called fire air.
9. He proposed Charles Law.
10. Made an early hypothesis about the law of conservation of energy.
11. He established the concept of absolute zero temperature.
12. Published the first modern representation of the periodic table.
13. He discovered the noble gases.
14. He discovered the source of radiation as decaying atoms.
15. Proposed an early nuclear model of the atom that had electrons orbiting a nucleus.
16. He discovered the exact number of molecules in a mole.
17. Proposed an early model of the periodic table that only had 28 elements.
18. Discovered the first synthetic dye.
19. He was the first person to accurately measure atomic weights.
20. Discovered cesium and rubidium; discovered the antidote to arsenic poisoning.
21. Codiscovered the chemical elements radium and polonium.