How Has Atomic Theory Changed Over The Years

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Recommended: The historical development of atomic structure

Development of the atom model from early days to present days
Scientists have come up with a range of different theory about the atomic structure through the past centuries. As new advanced technologies have invented through their research of atom, it is easier for scientist to create new theories throughout the future. This essay will explain the different changes of` atomic theory in order from the early days till now.

The atomic theory was first explained by Leucippus. He is a Greek philosopher who lived around the 400 B.C. During that era, people are trying to understand the way an object is made. Another Greek philosopher who said ‘it is possible to subdivide a material into smaller and smaller parts’, but according to Leucippus theory, therefore, ‘eventually you …show more content…

He found out that the atom is mostly empty space, with electrons orbiting a fixed positively charged nucleus in set, predictable paths. His famous experiment was the gold foil experiment. His experiment was to emit alpha particles towards a thing piece of gold. When the radiation was shooting out, it was detected by the fluorescent and was able to make the alpha particles visible through a viewing of a microscope. For the results, most of the alpha particles went through the gold foil, which means that they mainly consist of empty space. A small number of alpha particles were deflected slightly which suggested that the nucleus was positively charged. Only a varied number of alpha particles were bounced back, which means that most of the mass is concentrated in the nucleus because it needed a strong repulsion in order to bounce back.

A physiology Niels Bohr, who happened to study about the atomic theories with Rutherford, did a modification with the model and proposed that the electrons orbit the nucleus at different energy levels. The electrons are able to move from one level to another by gaining or losing their energy

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