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Uranium Essay Research Paper UraniumUranium was discovered

Uranium Essay, Research Paper


Uranium was discovered in the 1700’s in the coal mines of bohemia and

Jachlovikna. Uranium’s atomic number is 92, its Symbol is U and the atomic mass

of uranium is 238.0289. Miners called it Pechblende meaning, Pechblende, from

the German words pech, which means either pitch or bad luck, and blende, meaning

mineral Uranium’s first full analysis was done on 1789 by Martin Klaproth, a

self-taught well educated german chemist. Klaproth, having extracted from

pitchblende what he called ‘a strange kind of half metal’ (he had only isolated

its oxide), he resisted the temptation to give his own name to the new element,

which was quite customary at the time. William Herschel gave uranium its name

from the last planet founded in are solar system at the time, he named it Uran,

which in its final form became uranium, a name which today is known worldwide

while klaproth’s own fame has faded. Uranium is as dense as gold. Uranium, was

first prepared with some difficulty, in 1841 by the french chemist Eug?ne

Peligot, using thermal reaction of tetrachloride with potassium. Later in 1870,

an important fact was established: uranium is the last and heaviest element

present on earth. This was demonstrated by Dimitri Mendeleev in his famous

perodical classification of the elements by chemical properties and increasing

atomic mass. Experimentation with uranium lead to many discoversies such as the

X-ray by Wilhelm R?ntgen, on November 8, 1895.

Wilhelm R?ntgen, was awarded the first Nobel prize in 1901 for the development

of the X-ray. Uranium is weakly radioactive, decaying slowly but inexorably at

the rate of one milligram per tonne per year. It is transformed into inactive

lead through a chain of radioelements or daughters, each of which has a

characteristic disintegration rate, a constant of nature that man has never been

able to alter. The proportion of each radioelement in the ore is inversely

proportional to its rate of disintegration. Radium is the fifth radioactive

descendant in the chain from uranium to lead, its daughter is the gas radon, and

polonium is the last radioelement before lead. The discovery of Uranium changed

the world as we knew it, from its physical and chemical properties we came about

the X-ray, following down the line, chemists and scientists used Uranium to make

weapons of mass destruction, (i.e the Atom bomb).


1. Comptons Online Encyclopedia

2. Websters Dictionary

3. Merill, Physical Science book

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