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Name: Michael
Status: educator
Age: 30s
Location: N/A
Country: N/A
Date: 1999 

Please explain the basic mechanics of how scientists discover new chemical elements.

I've had students working on it since September. I've verified the information that they've come up with. I guess what we really want to know is:

1)Exactly how does a proton accelerator work?, and

2)How do scientists prove that the nucleus of a new atom has the required number of protons in order to be classified as a new element?

How to discover new elements? Well since all below say number 110 have been "discovered", really this is part history, part science question. I always enjoyed reading The Ascent of Man by Jacob Brownowski (spelling?), its a combination of the two. (also was a PBS TV show long ago). It tells about Mendelev and how he invented the periodic table.

This book also discusses your third question about required number of protons. These were red hot questions about 90 years ago, so its very interesting to read how the real people worked this thru.. In that Ascent of Man book see also the short write up on H.G.Moseley, 1913. He showed how x-rays can tell one element from the next in a very regular, monotonic, simple way that matched the newly proposed Bohr model of the atom (1912).

Also don't forget the chemical approach to all this. Because an atom has x protons, it must also have x electrons. Those x electrons have to fill in the atom in a regular way. The way they fill in determines the chemistry of the atom, so that chlorine with 17 is very reactive, while argon with 18 is inert. So early chemists/physicists answered your question in reverse,by showing that the chemistry is different, so therefore thenumber of protons is different.

S. Ross

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