... Towards the end of the 19th century, JJ Thompson, an English physicist discovers the corpuscle, an elementary particle which we today refer to as the electron. A few years later, in 1904, Thomson, based on his experiments with cathode ray tubes, proposes the Plum Pudding Model of the atom, which ... around the nucleus to explain how they remained stable. In this model, each orbit is associated with a particular energy level (shell), and the electron is able to change energy levels or orbits through the emission or absorption of energy in specified and discrete amounts (called quanta). Bo...

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... fraction of a second; then it is immediately drawn back toward the nucleus, to its original orbital. As it returns to its original orbital, the electron releases the extra energy in the form of a photon, in this case a light photon. The wavelength of the emitted light depends on how much energy ... is released, which depends on the position of the electron. Different kinds of atoms will release different sorts of light photons meaning the color of the light is determined by what kind of atom is excited ... higher energy levels. When the electrons return to their original energy level, t...

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... an atom gains or loses energy, the change is expressed by the movement of electrons. When something passes energy on to an atom, an electron may be temporarily boosted to a higher orbital (farther away from the nucleus). The electron only holds this position for a tiny fraction of a second; almost immediately, it is drawn back toward the nucleus, to its original orbital. As ... it returns to its original orbital, the electron releases the extra energy in the form of a photon, in some cases a light photon. The earliest stimulated-emission device developed in 1954, it was a microwave mase...

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... of Illinois achieved "coherent phase control of hydrogen disulfide molecules by firing ultraviolet lasers of different wavelengths at them." Laser chemistry looks promising and is a way that chemistry is still being expanded. Again, chemical reactions are the main part of a branch of chemistry. Here again, scientists are playing with chemical reactions. In April of 1995, a chemist named Peter Schultz and a physicist ... wanted results. This discovery opens doors for nanoengineering and material sciences. It gives a good view of what happens, one molecule at a time. Chemical reactions ar...

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... Rutherford had just discovered the nucleus of the atom from analysis of his team's gold foil experiments. Niels made the main breakthrough by proposing that the orbital momentum of an electron in orbit around a nucleus is quantized, so that it can only jump from one allowed orbit to another, and not spiral steadily into the nucleus. The energy associated with these ... the line spectrum of the hydrogen atom. His explanation of the line spectrum of the hydrogen atom led Bohr formulate his famous principle of complementarity. This principle holds that the electron could be regarded in two...

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... are metals and the others are nonmetals. A few examples are oxygen, iron, gold, chlorine, and uranium. Fluorescence: Electrons absorb energetic radiation (for example ultraviolet light) raising an electron to a higher "Bohr" orbit. The energized electron soon drops down in a series of steps through lower energy states and in the process releases photons at lower energy states corresponding to visible light. The bright ... it takes for half the nuclei of a radioactive element to undergo decay to another nuclear form. Magnetic field: All magnetic fields are created by moving electric char...

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... will affect the reaction. Even a slight change in any one of these could change the reaction. There are many branches of Chemistry that use chemical reactions, infact, almost all of them. Here are some examples. Photochemistry is one branch of chemistry that deals with chemical reactions. It has to do with the radiant energy of all kinds formed during chemical reactions. Photochemists ... of Illinois achieved "coherent phase control of hydrogen disulfide molecules by firing ultraviolet lasers of different wavelengths at them." Laser chemistry looks promising and is a way that chemistry ...

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... they have a tendency to bounce around. As a result the bouncing atoms collide with other materials and mess up the entire structure (Davidson A1). Taken in hand with the movement of electron charges, many regard nanotech as impossible (Garfinkel 106). But this is not the entirety of the obstacles confining nanotech development. One major set-back is the fact that the nanostructures ... ...

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... carbon. Less heat in now created. You can now make a light bulb turn on using the electrons flowing through the wire that you connected. Heat energy is now made into electron motion The electrons now go through the trouble to go to the carbon rod because they find it much easier to connect with hydrogen. Eventually, the zinc rod disappears completely ... ...

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... a radioactive atom that is undergoing spontaneous disintegration. Beta particles do not exist in the nucleus but are created on disintegration, beta decay, when a neutron converts to a proton to emit an electron. Beta particles are more penetrating than alpha particles, but less so than gamma radiation; they can travel several meters in air, but are stopped by 2-3 mm of aluminum. They are ... ...

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