Mar 18, 2021 06:44 PM
The idea that matter was composed of elements and atoms began with the ancient Greeks. However, atomism, as they called it, was a competing theory of matter that vied with the elements theory. It was Empedocles who first argued that all matter was made up of earth, fire, air and water. These four elements later were extended by Aristotle to include a fifth, Quintessence or ether. This was based on the fact that he believed that everything above the moon's orbit was perfect and was therefore made up of something less worldly.
It was not until the 1800's that the idea of the atom was revived by English Physicists like J.J Thomson and then Ernest Rutherford in the early 1900's that the structure of the atom was complete. The Plum Pudding model assumed a positively charged diffuse "matrix" that was occupied by the electrons which were known to exist at the time. This was later replaced by the Solar system model but was seen to be problematic due to the fact that accelerating electrons would cause the atom to collapse and radiate energy in the form of photons.
By firing a stream of Alpha particles at a thin gold foil did a far more accurate picture of the atom come about. But it was not until the advent of Quantum Physics did the model of the atom gain any significant degree of accuracy.
It was not until the 1800's that the idea of the atom was revived by English Physicists like J.J Thomson and then Ernest Rutherford in the early 1900's that the structure of the atom was complete. The Plum Pudding model assumed a positively charged diffuse "matrix" that was occupied by the electrons which were known to exist at the time. This was later replaced by the Solar system model but was seen to be problematic due to the fact that accelerating electrons would cause the atom to collapse and radiate energy in the form of photons.
By firing a stream of Alpha particles at a thin gold foil did a far more accurate picture of the atom come about. But it was not until the advent of Quantum Physics did the model of the atom gain any significant degree of accuracy.