The evolution of the Atomic Model
The word atom was first used around 330 BC and that is when the atomic began to slowly develop over time. Democritus was the first person to ever use the word atom and he briefly described the "Atom" and how it was what matter was made up of but no one payed any attention to this idea then. Thousands of years later, John Dalton, a famous English scientists was the first to develop an Atomic Theory. Dalton's theory stated, 1) All matter is made of tiny particles called atoms that are indivisible. 2) All atoms of a given element are identical. 3) Atoms of different elements are different in mass and in properties. 4) Atoms can combine into a ratio to form a compound. These atoms can be separated, combined, or rearranged in chemical reactions. Which we now know both parts 1 and 2 to be incorrect. After Dalton, J.J. Thomson expanded on his simple Atomic model, a sphere with no smaller particles, and his atomic theory. Thomson did this by conducting the Cathode Ray Tube Experiment and discovering the first subatomic particles, electrons! With finding these electrons within atoms, J.J. Thomson has proven the first part of Dalton's atomic theory wrong because atoms are now in fact divisible. Although Thomson found this his model was still off to the modern model we know today. His model consisted of simply electrons in a "jelly" like substance with a positive charge that neutralized the negative charge of the electrons. This was known as the "plum pudding" model.
After experimenting and testing the plum pudding model, Rutherford found that there wee flaws and something wrong with the model Thomson created. Rutherford began conducting more through research and discovered the nucleus! There was a nuclear theory that was made by Rutherford and his model was named the Nuclear model of a Atom. This was yet another big step in the evolution of the atomic model. So the model created by Rutherford was a spherical atom with a nucleus with only positively charged subatomic particles which were named protons. and around the nucleus were the electrons. Then only years later, one of Rutherford's students, Niels Bohr, expounded and changed the atomic model as well. Bohr found that electrons are not just distributed to surround the nucleus but actually orbit around the nucleus. Lastly, after the discovery of the neutron by James Chadwick, Erwin Schrodinger creates and equation to show the likelihood of electrons to be in a certain area at once. Erwin learned that electrons are most often found in the more dense portion of the electron cloud that Rutherford had explained. With this mathematical equation a new model of the atom was invented by Erwin which is know and the Quantum Mechanical Model of the atom.
Although it took hundreds of thousands of years to develop the atomic model we now know today we know a good amount of the information about the atom and we are still learning and researching more. Each one of these men had their own incredible discovery that led society one step closer into learning the foundations of the building block of chemistry.
After experimenting and testing the plum pudding model, Rutherford found that there wee flaws and something wrong with the model Thomson created. Rutherford began conducting more through research and discovered the nucleus! There was a nuclear theory that was made by Rutherford and his model was named the Nuclear model of a Atom. This was yet another big step in the evolution of the atomic model. So the model created by Rutherford was a spherical atom with a nucleus with only positively charged subatomic particles which were named protons. and around the nucleus were the electrons. Then only years later, one of Rutherford's students, Niels Bohr, expounded and changed the atomic model as well. Bohr found that electrons are not just distributed to surround the nucleus but actually orbit around the nucleus. Lastly, after the discovery of the neutron by James Chadwick, Erwin Schrodinger creates and equation to show the likelihood of electrons to be in a certain area at once. Erwin learned that electrons are most often found in the more dense portion of the electron cloud that Rutherford had explained. With this mathematical equation a new model of the atom was invented by Erwin which is know and the Quantum Mechanical Model of the atom.
Although it took hundreds of thousands of years to develop the atomic model we now know today we know a good amount of the information about the atom and we are still learning and researching more. Each one of these men had their own incredible discovery that led society one step closer into learning the foundations of the building block of chemistry.
The improvement of each model
Originally the only thing that an atom was was a word used by a guy in 330 BC. Then the atom gained a theory as well as a model in the early 1800s. Dalton's atomic theory, although only 50% of it was correct sparked the interest in the world to solve the mystery of what makes up matter. The atom went from a small particle of nothing to a particle that contained charges and subatomic particles, i.e. electrons. Then years later we learned about the positively charged subatomic particles called protons as well as their combination to make a nucleus. The discovery of the nucleus was ground breaking and also created the Nuclear Theory as well as the discovery of the electron cloud. Then barely any time passed and we learned that the subatomic particles with negative charges, electrons, orbit the nucleus. Once discovering the subatomic particles that have no charger at all, neutrons, we discovered lastly an equation that proves electrons are wavelike and can give you the possibilities of and electron's placement within the atom. We learned more about the electron cloud and how in the more dense parts of the cloud is where electrons will most likely be. So overall we went from knowing from a sphere shape that was called and atom made up matter to a more in depth description and definition as well as all the subatomic particles, the equation to predict their placement as well as the discovery of the nucleus was all impeccable despite the amount of time it took!