atomic model timeline - part 2.pptxphysical science

atoms

1. Planetary model: Niels Bohr Electrons orbit the nucleus in orbits that have specific size and energy. The energy of the orbit is related to its size. The lowest energy is found in the smallest orbit. Electrons reside in orbits. They move between each shell when gaining or losing energy. When gaining energy, electrons move to farther orbit from the nucleus. When losing energy, electrons move to closer orbit from the nucleus.

2. Quantum Mechanical Model: Erwin Schrödinger Electrons don’t move around the nucleus in orbits. Electrons exist in specific energy levels as a cloud. The electron cloud is the region of negative charges, which surrounds the nucleus. Orbital : The region with a high probability of containing electrons.