Einsteinium discovery

These elements have all been named for famous scientists or for the places of their creation. For example, americium, berkelium, and californium were named after obvious geographical locations. Nobelium was named for the Nobel Institute, although later study proved it was not really created there. Curium was named for Marie Curie, the discoverer of radium. Einsteinium was named for the famous physicist, Albert Einstein. Fermium and lawrencium were named for Enrico Fermi and Ernest O. Lawrence, who made important discoveries in the field of radioactivity. Mendelevium was named for the discoverer of the periodic chart. 

All isotopes of medelevium have been synthesized by other nuclear reactions since its discovery. They are prepared by bombarding uranium, einsteinium, and californium isotopes with heavy ions, such as boron-11, carbon-12 and carbon-13. 

FERMIUM. ICAS 7440-72-4). Chemical element symbol Fm. at. no. 100. at. wt. 257 (mass number of the most stable isotope), radioactive metal of the Actinide series, also one of the Transuranium elements. During Ihe period 1953- 1954. a group of scientists at the Nobel Institute of Physics (Stockholm) bombarded U with l60 ions, producing and isolating a 30-min alpha emitter. Ibis was called -5"l(X). However, discovery of element 100 was noi claimed at that time. Subsequently, the isotope was identified and the 30-miu half-lile conlirmed. Both fermium and einsteinium were formed in a thermonuclear explosion that occurred in the South Pacific in 1952. The elements were identified by scientists from the University of California s Radiation Laboratory, the Argonne National Laboratory, and die Los Alamos Scientific Laboratory. It was observed that very heavy uranium isutopes lhal resulted from the action of the instantaneous neutron flux cm uranium (conlaincd in the explosive device) decayed lo form Es and Fm, The probable electronic configuration of... 

The discovery of fermium (also einsteinium) was not the result of very carefully planned experiments, as in the cases of the other trans uranium elements, bill fermiuni and einsteinium were found in Ihe debris of an atomic weapon lest in the Pacific in November 1952. Researchers, using the Oak Ridge High Flux Isotope Reactor (HFIR) which produced 3.2-hour " Fm. determined ihe magnetic moment of the atomic ground state of the neutral fermium atom with a modified atomic beam magnetic resonance... 

Figure 15.8 Original elution data corresponding to the discovery of mendelevium, February 18, 1955. The curves for einsteinium-253 (given the old symbol E253) and californium-246 are for a-particle emission. (Dowex 50 ion exchange resin was used, and the eluting agent was ammonium a-hydroxyisobutyrate.)...

Einsteinium was discovered by a research team from the University of California at Berkeley. The team was led by Albert Ghiorso (1915-). The element was discovered in the ashes after the first hydrogen bomb test in November 1952 at Eniwetok Atoll, Marshall Islands, in the Pacific Ocean. The discovery was a remarkable accomplishment because no more than a hundred millionth of a gram of the element was present. It was detected because of the characteristic radiation it produced. 

After the discovery of uranium radioactivity by Henri Becquerel in 1896, uranium ores were used primarily as a source of radioactive decay products such as Ra. With the discovery of nuclear fission by Otto Hahn and Fritz Strassman in 1938, uranium became extremely important as a source of nuclear energy. Hahn and Strassman made the experimental discovery Lise Meitner and Otto Frisch provided the theoretical explanation. Enrichment of the spontaneous fissioning isotope U in uranium targets led to the development of the atomic bomb, and subsequently to the production of nuclear-generated electrical power. There are considerable amounts of uranium in nuclear waste throughout the world, see also Actinium Berkelium Einsteinium Fermium Lawrencium Mendelevium Neptunium Nobelium Plutonium Protactinium Rutherfordium Thorium. 

Then there are the people who find their eternal memorial in the kingdom. Lecoq, as we have seen, has had his little joke with gallium. Most people don t presume to give their own names to elements, and the other personal names have all been bestowed by committee in the nominee s honor. It is appropriate that the southern shoreline, including the southern strip of the Southern Island, should commemorate forever—or for as long as we exist— the contributions of Albert Einstein (einsteinium), Enrico Fermi (fermium), Dmitri Mendeleev (mendelevium), Alfred Nobel (nobelium, for stimulation to discovery, maybe, rather than discovery itself), and Ernest Lawrence... 

The history of syntheses saw its periods of breakthroughs and slack periods. The first breakthrough period was from 1940 to 1945 when four transuranium elements were synthesized, namely, neptunium (Z = 93), plutonium (Z = 94), americium (Z = 95), and curium (Z = 96). The period till 1949 was a slack time and no new elements were discovered. In the next breakthrough period from 1949 to 1952 four more transuranium elements were added to the periodic system, namely berklium (Z = 97), californium (Z = 98), einsteinium (Z = 99), and fermium (Z = 100). In 1955, fifteen years after the synthesis of the first transuranium element, one more element, mendelevium (Z = 101), was synthesized. The next 25 years saw much less syntheses and only six new elements appeared in the periodic system. Here scientists encountered an entirely new situation and many former criteria for evaluating discoveries of elements proved inapplicable. 

Thus, the discoveries of einsteinium and fermium were, so to say, unplanned. 

Some basic chemical properties of the first transuranium elements became already evident in the discovery experiments, in which chemical separations played a crudal role. With time, a vast amount of information has been amassed on the chemistry of the elements available in macro quantities, i.e., all the elements through californium and, to a lesser degree, einsteinium (see, e.g., Katz et al. 1986). 

The new discoveries gave Seaborg and his colleague new targets for bombardment Einsteinium was reacted with hehum ions. The new element Md, mendelevium, was formed, in 1955 at the University of California. 

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