Nobelium

"Nobelium is a synthetic element with the symbol No and atomic number 102. It was first correctly identified in 1966 by scientists at the Flerov Laboratory of Nuclear Reactions in Dubna,Soviet Union. Little is known about the element but limited chemical experiments have shown that it forms a stable divalent ion in solution as well as the predicted trivalent ion that is associated with its presence as one of the actinides."

"The appearance of this element is unknown, however it is most likely silvery-white or gray and metallic. If sufficient amounts of nobelium were produced, it would pose a radiation hazard. Some sources quote a melting point of 827 °C for nobelium but this cannot be substantiated from an official source and seems implausible regarding the requirements of such a measurement. However, the 1st, 2nd and 3rd ionization energies have been measured. In addition, an electronegativity value of 1.3 is also sometimes quoted."

"The discovery of element 102 was first announced by physicists at the Nobel Institute in Sweden in 1957. The team reported that they created an isotope with a half-life of 10 minutes, decaying by emission of an 8.5 MeV alpha particle, after bombarding ²⁴⁴Cm with ¹³C nuclei. The activity was assigned to ²⁵¹No or ²⁵³No. The scientists proposed the name nobelium(No) for the new element. Later they retracted their claim and associated the activity to background effects."