We have learned about the tiniest particle of matter is an atom, but really the teeniest part of matter is the electron. Its symbol is e−. The electron is called a "subatomic" particle and may move as fast as the speed of light. The electricity that powers radios, motors, and many other things consists of many electrons moving through wires or other conductors. electrons in an atom exist in a number of electron shells surrounding the central nucleus. Each electron shell is given a number 1, 2, 3, and so on, starting from the one closest to the nucleus (the innermost shell). Each shell can hold up to a certain maximum number of electrons. The distribution of electrons in the various shells is called electronic arrangement (or electronic form or shape). Electrons in their shells round an atom are the reason for chemical reactions. Complete outer shells, with maximum electrons, are less reactive. Outer shells with less than maximum electrons are reactive. The number of electrons in atoms is one way the Periodic Table is ordered. In laboratory conditions, the interactions of individual electrons can be observed by means of particle detectors, which allow measurement of specific properties such as energy, spin and charge. In one instance a Penning trap was used to contain a single electron for 10 months. (Who would think of trapping an electron?) The first video images of an electron's energy distribution were captured by a team at Lund University in Sweden, February 2008. The scientists used extremely short flashes of light, called attosecond pulses, which allowed an electron's motion to be observed for the first time. The distribution of the electrons in solid materials can also be visualized. The video couldn't be posted here, but here is a computer visual of the electron distribution of the Lithium ion.
Humans knew something electrical was going on when they could slide their feet across a rug and zap someone. Probably in the past, the way past, some humanoid rubbed some amber (mineralized tree pitch hardened) against his fur coat and zapped his kid. I bet that brought hours of fun for the humanoids!
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Mrs. TaylorI love science! Everything about the world is interesting and never boring. I love to study plants, animals, insects, and people. My favorite subjects are my students who are the most unique organisms on the planet! Categories |