@etstudyteam: Before the modern quantum model, Rutherford proposed the nuclear model which most of us know, followed by Bohr’s planetary model, where electrons were thought to orbit the nucleus in fixed energy levels. Then Louis de Broglie proposed that electrons have wave-like properties, introducing the idea of matter waves. Erwin Schrödinger built on this wave nature and developed the wave equation that became the foundation of quantum mechanics, replacing fixed electron paths with orbitals cloud-like regions where an electron is most likely to be found. Finally, Heisenberg’s uncertainty principle showed that we cannot simultaneously know an electron’s exact position and momentum, completing the shift from definite orbits to the probabilistic quantum mechanical model. #etstudy #ethiopian_education #physics #quantum #chemistry