Beginning of Essay
was discovered in the 1700's in the coal mines of bohemia and Jachlovikna. 's atomic number is 92, its Symbol is U and the atomic mass of is 238.0289. Miners called it Pechblende meaning, Pechblende, from the German words pech, which means either pitch or bad lu ....

Middle of Essay
.... 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 Röntgen, on November 8, 1895. Wilhelm Röntgen, 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 radi ....