Ununpentium

Symbol: Uup

Category(post transition metal)

Density at 25°C: solid:  n/a

Also known as element 115, this is a very short lived synthetic element with a maximum half life of around 200ms(milliseconds).  This is a particularly challenging element to produce. This is because it is hard to get more neutrons into it to make it more stable.


update: Now officially known as Moscovium (Mc) after Moscow, Russia.