Atomic Theory Essay

1040 Words 4 Pages
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…
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 …show more content…
For example if you melt copper down into its liquid form, it is still copper except the physical appearance is changed. Also with physical changes, you are able to reverse its change to a degree. The copper will change back to normal, and if water is frozen or boiled, it can be reversed back to its starting point. On the other hand chemical changes completely change the object and making the change irreversible. When a log is burned, it turns to ash. This is a chemical change because the objects chemical composition is different and also it will never be able to reverse itself back into a

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