Page 49 - Curriculum Visions Dynamic Book

Einsteinium (Es)
Element 99.An artificial transuranium element in the actinide series in the Periodic Table. It was the seventh transuranic element of the actinide series to be discovered.
It was first identified from the debris of thermonuclear bomb tests that occurred in the Pacific Ocean in 1952. It is highly radioactive.
Discovery
It was discovered in 1952 by Albert Ghiorso and others at Argonne, Los Alamos Labs, New Mexico and the University of California at Berkeley.
The first isotope discovered had an atomic mass of 253 and a half-life of
20 days. More research has discovered
14 isotopes.The one with the longest half-life (of 275 days) is einsteinium-254.
Technology
Because it has only been isolated in such tiny amounts, nobody has been able to make use of it.
Geology
Because it is an artificial element, it does not occur naturally.
Biology
Since it is an artificial element it has no role in living things. It is, however, radioactive and therefore potentially hazardous to health.
Key facts...
Name: einsteinium
Symbol: Es
Atomic number: 99
Atomic weight: 252
Position in Periodic Table: inner transition metal;
period 7 (actinide series)
State at room temperature: solid
Colour: unknown
Density: n/a
Melting point: 860°C
Boiling point: n/a
Origin of name: named after Albert Einstein Shell pattern of electrons: 2–8–18–32–29–8–2
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