Einsteinium-253

The electrochemical behavior of einsteinium has received only minimal literature coverage. Nugent etal. [175] employed 

SYMBOL Es PERIOD 7 SERIES NAME Actinide ATOMIC NO 99 

ATOMIC MASS 252 amu VALENCE 2 and 3 OXIDATION STATE +2 and -1-3 NATURAL STATE Solid 

ORIGIN OF NAME Named after and in honor of the famous physical scientist Albert Einstein. 

ISOTOPES There are total of 20 isotopes of einsteinium. Einsteinium is not found in nature. All the isotopes are radioactive and are produced artificially. Their half-lives range from eight seconds to 472 days. None have exceptionally long half-lives. 

Energy Levels/Shells/Electrons Orbitals/Electrons 

It is one of the ironies of twentieth century science that, although his work on the photoelectric effect helped to advance quantum mechanics, Einstein came to be its chief critic. It was his antagonism toward the probabilistic and nondeterministic nature of quantum phenomena that prompted Einstein to make the often-quoted remark, I cannot believe that God would choose to play dice with the universe.  

Einstein s explanation of the photoelectric effect was not his only contribution to chemistry. His Ph.D. dissertation, submitted in 1905, was entitled A New Determination of Molecular Dimensions. His investigation of Brownian motion (the random movement of microscopic particles suspended in liquids or gases) was intended to establish the existence of atoms as being indispensable to an explanation of the molecular-kinetic theory of heat. And the concept of relativity has shed light on the motions of electrons in the core orbitals of heavy elements, see also Quantum Chemistry. 

Abraham (1982). Subtle Is the Lord The Science and Life of Albert Einstein. New York Oxford University Press. 

Stachel, John J., ed. (1998). Einstein s Miraculous Year Five Papers that Changed the Face of Physics. Princeton, NJ Princeton University Press. 

Friedman, S. Morgan. Albert Einstein Online. Available from http //www.westegg, com/einstein/ . 

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The use of larger particles in the cyclotron, for example carbon, nitrogen or oxygen ions, enabled elements of several units of atomic number beyond uranium to be synthesised. Einsteinium and fermium were obtained by this method and separated by ion-exchange. and indeed first identified by the appearance of their concentration peaks on the elution graph at the places expected for atomic numbers 99 and 100. The concentrations available when this was done were measured not in gcm but in atoms cm. The same elements became available in greater quantity when the first hydrogen bomb was exploded, when they were found in the fission products. Element 101, mendelevium, was made by a-particle bombardment of einsteinium, and nobelium (102) by fusion of curium and the carbon-13 isotope. 

Albert Einstein) Einsteinium, the seventh transuranic element of the actinide series to be discovered, was identified by Ghiorso and co-workers at Berkeley in December 1952 in debris from the first large thermonuclear explosion, which took place in the Pacific in November, 1952. The 20-day 253Es isotope was produced. 

In 1961, enough einsteinium was produced to separate a macroscopic amount of 253Es. This sample weighted about O.OlMg and was measured using a special magnetic-type balance. 253Es so produced was used to produce mendelevium (Element 101). 

About 3Mg of einsteinium has been produced at Oak Ridge National Eaboratories by... 

The targets were then removed for chemical separation of the einsteinium from californium. 

Fourteen isotopes of einsteinium are now recognized. 254Es has the longest half-life (275 days). 

Tracer studies using 253Es show that einsteinium has chemical properties typical of a heavy trivalent, actinide element. 

Fourteen isotopes are now recognized. 258Md has a half-life of 2 months. This isotope has been produced by the bombardment of an isotope of einsteinium with ions of helium. Eventually enough 258Md should be made to determine its physical properties. 

Each of the elements has a number of isotopes (2,4), all radioactive and some of which can be obtained in isotopicaHy pure form. More than 200 in number and mosdy synthetic in origin, they are produced by neutron or charged-particle induced transmutations (2,4). The known radioactive isotopes are distributed among the 15 elements approximately as follows actinium and thorium, 25 each protactinium, 20 uranium, neptunium, plutonium, americium, curium, californium, einsteinium, and fermium, 15 each herkelium, mendelevium, nobehum, and lawrencium, 10 each. There is frequently a need for values to be assigned for the atomic weights of the actinide elements. Any precise experimental work would require a value for the isotope or isotopic mixture being used, but where there is a purely formal demand for atomic weights, mass numbers that are chosen on the basis of half-life and availabiUty have customarily been used. A Hst of these is provided in Table 1. 

It is possible to prepare very heavy elements in thermonuclear explosions, owing to the very intense, although brief (order of a microsecond), neutron flux furnished by the explosion (3,13). Einsteinium and fermium were first produced in this way they were discovered in the fallout materials from the first thermonuclear explosion (the "Mike" shot) staged in the Pacific in November 1952. It is possible that elements having atomic numbers greater than 100 would have been found had the debris been examined very soon after the explosion. The preparative process involved is multiple neutron capture in the uranium in the device, which is followed by a sequence of beta decays. Eor example, the synthesis of EM in the Mike explosion was via the production of from followed by a long chain of short-Hved beta decays,... 

The effects of a rather distinct deformed shell at = 152 were clearly seen as early as 1954 in the alpha-decay energies of isotopes of californium, einsteinium, and fermium. In fact, a number of authors have suggested that the entire transuranium region is stabilized by shell effects with an influence that increases markedly with atomic number. Thus the effects of shell substmcture lead to an increase in spontaneous fission half-Hves of up to about 15 orders of magnitude for the heavy transuranium elements, the heaviest of which would otherwise have half-Hves of the order of those for a compound nucleus (lO " s or less) and not of milliseconds or longer, as found experimentally. This gives hope for the synthesis and identification of several elements beyond the present heaviest (element 109) and suggest that the peninsula of nuclei with measurable half-Hves may extend up to the island of stabiHty at Z = 114 andA = 184. 

Einsteinium, Es Workers at Berkeley, 1952 Found in debris of first Albert Einstein... 

Edison storage battery, 406 Einstein, Albert, 121 Einsteinium, oxidation number, 414 Elastic collision, 6 Electrical nature of atoms, 236 Electrical phenomena, 74 Electrical properties of condensed phases, 78... 

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