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Ununpentium is a chemical element. It is also named eka-bismuth. It has the symbol Uup. It has the atomic number 115. It is a superheavy element.

Ununpentium does not exist in nature. It is a synthetic element, made from a fusion reaction between americium and calcium.

Ununpentium is in the center of the theoretical island of stability. No stable isotopes of ununpentium have yet been found. Models predict that the stable isotope of ununpentium should have 184 neutrons. The stable isotope with 184 neutrons is 299Uup. The isotope that has been made has only 173 neutrons (288Uup).

History[change | change source]

On February 2 2004 a report that ununpentium and ununtrium were made was written in a journal named Physical Review C. The report was written by a team of Russian scientists at Dubna University's Joint Institute for Nuclear Research and American scientists at the Lawrence Livermore National Laboratory.[1],[2]

These people reported that they bombarded americium with calcium to make four atoms of ununpentium.

Scientists of Japan also report that they have made Ununpentium.

In May 2006 at the Joint Institute for Nuclear Research this element was made by another method and what the final products from radioactive decay were was found by chemical analysis.

Name[change | change source]

Ununpentium is a temporary IUPAC systematic element name.

Chemical properties[change | change source]

Not enough ununpentium has been made to measure its physical or chemical properties. It is thought that it would be a hard metal. It may have a low melting point of about 250 °C. It may be slightly colored.

Ununpentium is in the same group as bismuth but its chemical properties will be different. The chemistry of ununpentium will be very influenced by special relativity. It will make its properties different to the other elements in the periodic table that have a smaller atomic number.[3] One important difference from bismuth is the presence of a stable oxidation state of +I (Uup+). The (Uup+) ion is thought to have chemical properties like Tl+.

In popular culture[change | change source]

Ununpentium is inside the island of stability. This is probably why it is found in popular culture. It is more likely to be talked about in UFO conspiracy theories.

The most popular story about ununpentium is from Bob Lazar. It is not pseudoscience because it is a refutable theory, however Lazar's claims are not backed by any direct experimental evidence at this time.[4]

References[change | change source]

  1. Oganessian, Yu. Ts.; et al. (2004). "Experiments on the synthesis of element 115 in the reaction 243Am(48Ca,xn)291−x115". Physical Review C 69: 021601. doi:10.1103/PhysRevC.69.021601. http://link.aps.org/abstract/PRC/v69/e021601.
  2. Oganessian, Yu. Ts.; et al. (2005). "Synthesis of elements 115 and 113 in the reaction 243Am + 48Ca". Physical Review C 72: 034611. doi:10.1103/PhysRevC.72.034611. http://link.aps.org/abstract/PRC/v72/e034611.
  3. Keller, O. L., Jr.; C. W. Nestor, Jr. (1974). "Predicted properties of the superheavy elements. III. Element 115, Eka-bismuth". Journal of Physical Chemistry 78: 1945. doi:10.1021/j100612a015.
  4. Lazar Critique, D. L. Morgan.

Other websites[change | change source]