The Atomic Theory: The Physics Of The Atomic Theory

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Atomic Theory The atom is the smallest unit of an element. It is composed of two main parts. The nucleus is the central point of an atom. Compacted in that small space are neutrons and protons that constantly jiggle. Neutrons are uncharged particles that add mass to the nucleus without adding a charge. The protons are positively charged particles that are also located in the nucleus and symbolized as p+. The second part of an atom is the electron cloud. The electron cloud is a cloud of electron which surrounds the nucleus. The electrons are the third type of subatomic particle- along with protons and neutrons. Located outside of the nucleus, electrons are negatively charged. Due to their location and their ability to react with other atoms, electrons have a large effect on the reactivity and other characteristics of an atom. Over the years, atoms have been proposed to look like a multitude of things. However, the most recent model is of a tiny atom surrounded by a cloud of electrons. This …show more content…
Each new discovery brought a new point of view which caused someone to build a new model, using a mix of traditional ideas along with new theories. J.J. Thompson was the first to design a contemporary model of the atom. His model is referred to as the plum pudding model, because it mirrors a bowl of pudding with plums inside. The next great change to this came from Bohr. He used the concept of electrons circling around a nucleus in orbitals to create the planetary model. Today, the modern atom model is the cloud model. The electrons still revolve in orbitals, but it is now known that these orbitals are not an exact measure, they are simply the places where an electron is most likely to be. This concept has a basis in probability. Also, there are different orbitals, known as the s, p, d, and f orbitals. Each type carries a different number of

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