Atomic Theory History

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Within a little over two millenniums, the history of the atomic theory changed multiple times. In the very beginning, Democritus was the very first to propose the existence of the particle (H). The name he would give this particle was atomos. Aristotle believed that each element of the earth; water, air, fire, and earth, would gradually become small every time they were halved. This view held up for about 2,000 years. The next major change within the scientific field that concerned atoms was when John Dalton proposed his Atomic Theory in 1803. The atomic theory is, all matter is made up of atoms, atoms are indivisible and indestructible, and finally compounds are formed by two or more different kinds of atoms. J.J. Thomson, discovered that …show more content…
Thomson’s plum pudding model was correct, then the particles would shoot straight through the gold foil and only leave black marks on the direct other side of the foil. When Rutherford performed this experiment, he found that there were black marks on the sides of the foil that suggested that it reflected off of the gold foil along with appearing on the other side. With this experiment disproving J.J.’s model, Ernest proposed his own idea. His idea was that all of the positive charge and all of the mass of the atom occupies a rather small volume at the direct center of the atom. Also the most volume of the atom was from the empty spaces that electrons were found in. Another person who takes place in changing the history of atoms is Francis Aston. Aston was the first to study isotopes. He noticed that there are hydrogen atoms with mass numbers of 2 and 3 instead of the normal 1. James Chadwick made the most recent major discovery of the atom. In 1932, he discovered the neutron in the atom. James was a collaborator with Ernest Rutherford, and with this discovery it led to the discovery of fission and ultimately the atomic bomb (H). The modern atomic theory is that it has an orbital of electrons with the protons and neutrons within the middle. Typically depicted by the Bohr’s model …show more content…
The first model was just a sphere, and then the next was the plum pudding model, which J.J. Thomson proposed. But his model was soon disregarded when Ernest Rutherford performed his gold foil experiment (H). Finally with the help of Rutherford, Niels Bohr, created the current model in which atoms are shown. The Bohr Model is depicted as the protons and neutrons within the middle and then an orbital of electrons circling the nucleus (N). There are four fundamental forces that act upon the nucleus. The forces are, strong force, weak force, electromagnetic, and gravity (F1). The strong force holds the nucleus together and produces all of the interactions between all particles containing quarks (F2). The weak force holds the protons and neutrons together. Electromagnetic force binds electrons to the nucleus. Since electrons have a negative charge, and protons have a positive, electromagnetic force allows the two ends to pair binding to each other. Gravity is the force that holds us to the ground; this is significant because with the billions of billions of atoms that make up us, we can feel gravitational pull. The larger the body, the larger the pull we feel

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