e
was a mixture of zinc and iron compounds; however, this proved not to be
the case. Kalproth found an unknown element in his experimental
samples. He named this newly discovered, mystery element uranium,
after the also just discovered planet Uranus. Contrast to the belief
of Kalproth, he never succeeded in isolated his uranium. It only
existed in the compound pitchblende. Kalproth tried to react this compound, by the use of nitric acid and potash, in order to
isolate the Uranium. He believed he had done so when he discovered
black crystals on the bottom of his crucible. He claimed that these
were samples of metallic uranium. It wasn't discovered that these
black crystals were indeed not uranium, but the compound uranous oxide (UO2),
until well after Kalproth's lifetime in 1841. The French chemist
Eugène-Melchoir Péligot was reacting "pure uranium" with
uranium tetrachloride, UCl4, and
finding obscure ways that he had never seen before. The
only logical answer he could find that would explain the reaction was that
the so-called "pure uranium" everyone had dealt with for over 50
years was in fact not pure at all. It was uranous oxide.
With this new found knowledge, Péligot isolated uranium meta by heating
the uranous oxide compound with potassium. Now uranium was finally
isolated; however, its properties remained a mystery.
It wasn't
discovered until 55 years later, in 1896, the uranium was highly
radioactive. Henri Becquerel came to this conclusion when he
detected radioactive emissions from uranium with his newly
designed electrometer instrument.
Website Created By Jarad
Mason
March 30, 2003