Lawrencium Essay, Research Paper
Lawrencium
There are 109 known elements, and of those, 19 of them are artificially produced or synthetic. A synthetic element is made by bombarding atomic nuclei with neutrons or other particles. The element Lawrencium has been made in this manner. While scientists continue to work to create more elements, it should be noted that most synthetic elements are so unstable, that they are of theoretical value only, and have no known practical uses. This element was discovered at the Lawrence Radiation Laboratory, at The University of California in 1961 by Albert Ghiorso, Torbjorn Strikkland, Almon E Larsh, and Robert M. Latimer. The Element Lawrencium was named after the American physicist, Earnest Lawrence, inventor of the cyclotron particle accelerator in which sub-atomic particles are sent round and round in a circle at ever increasing speeds until they have enough energy to smash into an atom thereby creating a new atom. It is also a member of the actinide series, a series of chemically similar radioactive elements with atomic numbers ranging form 89 (actinium) through 103 (lawrencium).
Lawrencium is a manmade element of which, only a few atoms have ever been created. Lawrencium is made by bombarding particles of californium with particles of boron in a cyclotron, or other accelerator. The process is complicated and expensive. Bombarding curium, another artificial element in the actinide series, with helium, makes californium. Californium is then converted into lawrencium. Lawrencium is not only hard to make, it is very unstable. With a half life of three minutes, the most stable isotope, Lr 260, is hard to identify, and impossible to preserve. Unlike natural elements, lawrencium has remained a mystery. The normal physical and chemical properties of more stable elements have been observed, recorded, and described. Color, hardness, density and other characteristics are almost impossible to evaluate if only a few atoms of the substance exist. Merely counting and identifying individual atoms of lawrencium is difficult. Observing their properties is almost impossible. Some of the properties of lawrencium such as: melting point, boiling point, crystal structure, density, and color are unknown. Bentor, Yinion. Chemical Element.com-Lawrencium. Nov.21, 1999.
A material that looses half of its mass every three minutes is valuable only as a curiosity. It cannot be made into anything of use, and reactions with other chemicals are almost impossible to observe. Lawrencium is valuable only as an educational tool and for theoretical studies. Because of its instability Lawrencium is thought to have no biological role. Being radioactive, lawrencium is therefore toxic to living organisms, thereby limiting any possible biological uses. Lawrencium does not occur freely in nature. Only about 20 of the 109 elements are found free in nature. The rest occur in chemical combinations or in laboratory experiments. Lawrencium is also a transuranic element, meaning that the element has an atomic number greater than 92. There are many isotopes of Lawrencium but the key isotope is Lr 260 with the greatest half-life of three minutes. There are many other isotopes of lawrencium for example Lr 254 with a half-life of only 13 seconds. The most common oxidation state of the element lawrencium is Lr+3.
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