Théorie atomique

Study Notes

Democritus proposed the concept of "atomos" (indivisible particles) as the fundamental building blocks of matter.
John Dalton's atomic theory provided scientific evidence for atoms as solid, indivisible spheres that combine in fixed ratios to form compounds.
J.J. Thomson's plum pudding model suggested atoms are composed of negatively charged particles (electrons) embedded within a positively charged "soup."
De Broglie proposed the wave-particle duality of matter, suggesting that electrons exhibit both wave-like and particle-like properties.
Erwin Schrödinger's quantum mechanical model described electrons as waves and predicted their behavior using the Schrödinger equation.
Electrons occupy orbitals, regions of space where they are most likely to be found rather than fixed paths.
Werner Heisenberg's uncertainty principle states that it is impossible to precisely know both the position and momentum of a particle simultaneously.
Max Born's probabilistic interpretation explains the likelihood of finding an electron in a certain region of space using probability density.

Atom: The smallest unit of matter indivisible by ordinary chemical means.
Law of Conservation of Mass: The total mass of atoms in a chemical reaction remains constant.
Subatomic Particles: Atoms contain three key subatomic components:
- Electron: Negatively charged particle.
- Proton: Positively charged particle.
- Neutron: Neutral particle.
Isotopes: Atoms of the same element with the same number of protons, but different numbers of neutrons.
Average Atomic Mass: The weighted average mass of all isotopes of an element, calculated based on their relative abundance.