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Question:
How could one accelerate molecules to a very high speed without destroying them?



Replies:
The usual way to do this is to first partially ionize the molecule, so that it has an electric charge, then use an electric field to accelerate the particle, while keeping it on track with a magnetic field.

Molecules contain protons and electrons as part of their individual atoms. Usually there are the same number of each of these, one + charge the electrons minus charge. The molecule has no net charge. However if you can get even one electron off of the molecule then it has a net charge of minus one, and you can grab onto it with an electric force. You can get that one electron off in various ways but they often involve heating the substance, you almost "boil" the ions off.

Anyway, once you have stripped off the one electron, the molecule is charged. It can be pushed by an electric field. For example if you put two plates near each other, and attach each side to a battery, there would be a (weak) electric field going from one plate to another. Any ions caught inbetween would be pushed to the oppositely charged plate.

Finally, add a magnetic field -- just put a magnet near your two plates. The ion would try to move from one plate to another, being pushed by the electric field. But as it moved it would also "feel" the force of the magnet and would bend. Now you can bend the path of the ion down a pipe, and continually push it along by electric fields (some now can be radio waves etc), and speed the ion up more and more, aways keeping it aligned down the "pipe" with the magnets. We now have a fast moving molecule, for whatever purpose you want.

Dr. S. Ross



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