1 ene 1807 año - 1807
John Dalton proposes Dalton's atomic theory.
1. All matter is composed of tiny, invisible particles.
2. Each chemical element is composed of its own kind of particles, called atoms.
3. Atoms of an element are alike and have the same mass.
4. Atoms cannot be created or destroyed during physical or chemical changes.
5. Atoms unite in simple whole number ratios of form compounds (law of definite proportions).
Suggested that all molecules are binary, but had no evidence to support this.