Element Number 118

Symbol Uuo

Classed as an inert gas and is expected to have properties similar to those of radon and xenon.

Would presumably be a solid at 298 K

Probably metallic and silvery white or grey in appearance

In 1999 a research team at the Lawrence Berkeley National Laboratory in California bombarded lead-208 atoms with high-energy krypton-86 ions to create three atoms of element 118 with mass number 293 and a half-life of less than a millisecond.

Elements 118 and 116 were identified by accelerating a beam of krypton-86 ions to an energy of 449 million electron volts and directing the beam onto targets of lead-208. After 11 days work, just three atoms of the new element were identified. The production rates for element 118 are approximately one in every 1012 interactions.

No name has yet been suggested for element 118, which is therefore called ununoctium, from the Latin roots un for one and oct for eight, under a convention for neutral temporary names proposed by the International Union of Pure and Applied Chemistry (IUPAC) in 1980.

I'm not citing sources for the above, because these exact sentences are available from many places on the web, none of whom cite their source, so I have no idea who to cite.

according to
http://enews.lbl.gov/Science-Articles/Archive/118-retraction.html this was all a mistake. Ununoctium has never been synthesized.

ununseptium <-- ununoctium