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quote: Therefore an atom of Na has 11 protons & 11 electrons.
quote:It is necessary to use quantum mechanics to understand the behavior of systems at atomic length scales and smaller.For example, Newtonian mechanics say unlike charges attract so that an electron in a hydrogen atom which has a negative charge will be attracted to the nucleus which has a positive charge at great speed and collapse making it highly unstable. However, in the natural world the electron normally remains in a stable orbit around a nucleus seeming to defy classical electromagnetism.Quantum mechanics was initially developed to explain the atom and especially the orbit and position of the electron. Quantum mechanics uses probability distributions to explain such effects.Probability in the context of quantum mechanics has to do with the likelihood of finding a particle, such as an electron, in a particular region around the nucleus at a particular time. Therefore, electrons cannot be pictured as localized particles in space but rather should be thought of as clouds of negative charge spread out over the entire orbit. These clouds represent the regions around the nucleus where the probability of finding an electron is the largest.So in normal atoms with electrons in a stable orbit, the probability of the electron being at the nucleus is nearly zero according to the Heisenberg Uncertainty Principle.Therefore, the laws of quantum mechanics, unlike Newton's deterministic laws, lead to a probabilistic description of nature.
quote:Originally posted by simeonieWow sould sufer you are one smart girl/boy.
quote:I would have thought that chemists were only interested in how many electrons are in the outer shell as that determines valence. I don't see how different energy levels would interest them overly much. If I'm wrong, please enlighten me.
quote:Originally posted by Soul SurferOne final question remains why doesn't the electron ever lose all its energy and collapse onto the proton. Well we didnt know then but we now know that a proton is not a single static entity but three quarks batting around like mad things (they have more energy in their motion than in their rest mass!) so there is nothing stable for an electron to collapse on to.
Indeed, the classical approach cannot explain electron orbitals. However, I will try to give a very simple explanation.The electron does not ever merge with the proton in the atom because it does not have the energy to do it. This process is called "inverse beta decay" and it takes a lot of energy, and a neutrino. The proton is composed of 2 up quarks and a down quark, and the neutron is 2 down quarks and a up. (Or vice-versa, I can never remember.) Anyway, inverse beta decay is the process of combining a proton, electron, neutrino, and some energy into a neutron. The quarks must change flavor to do this. The whole process will not occur just because electrons are attracted to protons, electrically. That fact satisfies charge conservation, but is only part of the process.The orbital is a sort of resonance where each orbital level includes a quantum of energy. In addition, electrons are fermions, so they exclude each other in the atom, and always stay apart, in space and energy. In a broad-brush explanation this is why there are discrete orbitals."F = ma, E = mc^2, and you can't push a string."
"F = ma, E = mc^2, and you can't push a string."