1) Chemical element 2) Synthetic element
Found on
https://www.crosswordclues.com/clue/copernicium
Copernicium is a chemical element with symbol Cn and atomic number 112. It is an extremely radioactive synthetic element that can only be created in a laboratory. The most stable known isotope, copernicium-285, has a half-life of approximately 29 seconds, but it is possible that this copernicium isotope may have a nuclear isomer with a longer half...
Found on
http://en.wikipedia.org/wiki/Copernicium
No exact match found.
