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Question

I read that plasma is the fourth state of matter. In the same book, it stated that plasma was (basically) shattered particles, using fire as an example. Is this true?
Asked by: Aroura

Answer

A plasma, as defined by physicists, is a gas-like state of matter in which all (or many) of the electrons have been stripped from the nuclei they orbit. Atoms are not otherwise bound to each other as in a crystal or a metal. The negatively charged electrons and the positively charged nuclei (ions) co-exist and intermingle but do not, on the average, recombine to form stable, neutral atoms.

Actually, recombination of electrons and nuclei occurs continuously, which process is accompanied by the emission of light. This is why a plasma, such as occurs within a neon tube, or a flame, gives off a characteristic light. But, due to thermal energy (flame) or continued electrical excitation (neon tube), recombined electrons/ions are quickly knocked apart again, maintaining the average state of a mixture of free electrons and ions.

So, yes, the book is correct. A plasma consists, in effect, of 'shattered particles,' with 'shattered' meaning that the atoms are maintained, on the average, in an ionized condition, with the stripped electrons and resulting ions intermingling in a glowing, gas-like state.
Answered by: Warren Davis, Ph.D., President, Davis Associates, Inc., Newton, MA USA


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'The strength and weakness of physicists is that we believe in what we can measure. And if we can't measure it, then we say it probably doesn't exist. And that closes us off to an enormous amount of phenomena that we may not be able to measure because they only happened once. For example, the Big Bang. ... That's one reason why they scoffed at higher dimensions for so many years. Now we realize that there's no alternative... '

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(1947-)


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