Roentgenium

Roentgenium (pronounced /rɛntˈgɛniəm/, /rʌntˈdʒɛniəm/) is a man made, radioactive chemical element with the symbol Rg, and its atomic number is 111. It is a transition metal.

The element is named in honor of a German physicist Wilhelm Röntgen.

So far, it has not been found in nature. There seem to be 7 isotopes, and all of them are radioactive. They have a half life of between 1.6 milliseconds and 26 seconds. Because of the Inert pair effect, it could have a color similar to that of gold.

Roentgenium is in the same group as the precious metals copper, silver and gold, so it could easily be a hard metallic element if chemists ever create enough of it.

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