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430 BCE
Democritus "The origin of atom"
He used for the first time the word "atom" for atomos that means the building blocks of matter. They are indivisibles and unchangeable, with an empty space. Democritus experimented with a stone by cutting it in half until it reached a point where it could no longer be divided and each half has the same properties as the original stone. He didn´t make a structure of an atomic model. -
John Dalton "Billiard Ball Model"
Atoms are solid spheres indivisible and indestructible. In his experiment, he used a microscope called a scanning tunneling micrscope (STM) that produces images of individual atoms. Recognized atoms of a particular element differ from others elements. Atoms aren´t indivisible, are composed from subatomic particles. -
J.J. Thomson "Plum Pudding Model"
Discovered e- by the cathode rays experiment, which applied electrodes sealed in a glass tube. Atoms are postive spheres with e- in the surface. Recognized the electrons part of atoms. In his model, it didn´t had a nucleus and he didn´t explain it later. -
Rutherford "nuclear atom" model
in Rutherfords model he stated that the atoms have a small positive charged nucleus with electrons moving around and that atoms are mostly empty space he also discovered the protons he developed his atomic model using an experiment thats now known as the gold foil model in this experiment using a beam of alpha particles and a gold foil. -
Neils Bohr "Solar System"
In Bohr's atomic model he stated that electrons move a round the nucleus in circular orbits which he called energy levels. Hiis model is called the solar system model because the way the electrons orbit the nucleus reasambles the way the planets orbit the sun in the solar system. He also said that the electrons can not exist in between this orbits. -
Erwin Schrödinger "The Quantum Mecanical Model"
Erwin Schrödinger built upon the quantum mechanical model. He used a mathematical equation to describe the odds of finding the location of an electron, he called the layers, orbitals. These orbitals could be described as "electron density clouds". -
All atomic models
In order, from the beginning to the end.
