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Name: Sean
Status: student
Age: 10
Location: N/A
Country: N/A
Date: 1999 

I'm doing a report on elements and I'd like to do one on element #111 and if you could send me info about it, that would be great. In the book we use, element #111 isn't listed, so that's why I want to do it.

Hi Sean!

Element 111 was discovered recently (1994), so that's why it is not listed in "old" books. It was discovered at GSI, a German Laboratory, located in Darmstadt, by S.Hofmann, V.Ninov, F.P. Hessberger and others.

They gave it the name of Unununium, symbol: Uuu; Atomic number: 111; Atomic weight: 272. It should be at the same group as copper, silver, and gold ( group 11). Density: 53.5 g/mL; solid at 298K. It was prepared by shooting a nickel beam at a bismuth target and at the first experiment only a few of the atoms of 111 were detected, and they quickly decayed after the original collision.

These kind of experiments that allows the creation/discovery of new heavy elements are possible by the use of a multi-stage accelerator facility consisting of a whole system of linear and circular accelerators and beam pipes which interconnect the accelerators.This equipment exists at some big laboratories in the world.

By the way, do you know that other heavy (called super-heavy) elements were also created in labs? As the number 114?

Thanks for asking NEWTON

(Dr. Mabel Rodrigues)

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