General Information
| Atomic Number | 96 |
| Atomic Mass | 247.1g |
| Melting Point | 1613k |
| Boiling Point | 1340 °C |
| Density in Natural State | 13510kg m-3 |
| Natural Abundance | 0% |
| Curium is a synthetic element, meaning its not a natural occurring element, but man-made. | |
History
Curium, named after Pierre and Marie Curie, was first identified by three scientists Glenn T. Seaborg, Ralph A. James, and Albert Ghiorso in Berkeley, California. Directly after the discovery of Plutonium, Seaborg, James, and Ghiorso begin looking for elements 95 and 96. Seaborg had successfully predicted that the elements would have valences of +3 and chemical properties similar to Europium and Gadolinium.
In 1944, the group had "produced isotope 242 of element 96 (Curium-Cm) by bombarding plutonium-239 with alpha particles, or helium ions" (Exploring Chemical Elements and their Compounds 343):
239
Pu(a ,n)242Cm.The helium ion contributed two protons and two neutrons nucleus, thus increasing the atomic number by two and the atomic mass by 4. However, during the process, one neutron is lost, therefore, the net increase in atomic mass is only three, which produces Cm242.
In 1947, three years later, "visible amounts of curium were isolated" by Werner and Perlman (Exploring Chemical Elements and their Compounds 343). The experiment conducted produced the element by subjecting "americium-241 to prolonged neutron radiation," which resulted in americium-242 (Exploring Chemical Elements and their Compounds 343). Then spontaneous beta decay formed Curium-242. In 1951, the same workers prepared curium in its elemental form for the first time" ("Curium" Web Elements).