22 LIFE: ITS NATURE AND ORIGIN 



to a newly formed transuranic element 93, which ought to appear 

 in the Periodic Table in the same column with manganese. So 

 the irradiated uranium was dissolved with a manganese salt, and 

 the manganese was precipitated as Mn0 2 . This precipitate carried 

 with it part of the 13-minute and 90-minute activity, and many 

 scientists took up the quest for transuranic elements. 



In Germany, Otto Hahn (Nobel prize, 1946) and F. Strassman 

 made careful chemical separations of the dissolved uranium, and 

 were astonished to find radioactive atoms belonging to a number 

 of different elements, mostly those about the center of the Periodic 

 Table. These results were passed to Professor Niels Bohr, then 

 at Princeton University, reaching him at a meeting of the Ameri- 

 can Philosophical Society; and many nuclear physicists who 

 attended the meeting confirmed the results. 11 Professor Henry D. 

 Smyth states: 12 "Just before Bohr left Denmark, two of his col- 

 leagues, O. R. Frisch and Liese Meitner (both refugees from 

 Germany) had told him of their guess that the absorption of a 

 neutron by a uranium nucleus sometimes caused that nucleus to 

 split with the release of enormous quantities of energy, a process 

 that soon became known as 'nuclear fission.' Before considering 

 further details about the "atomic bomb," let us see whence comes 

 the huge amounts of energy released by nuclear fission. 



Albert Einstein and the Relation Between Mass and Energy 



About the end of the last century, Hendrik Antoon Lorentz 

 (Nobel prize, 1902) in developing an electron theory of matter, 

 assumed that the mass of an electron increases with increase in 

 its velocity; 123 but if the velocity could be equal to the speed of light 

 (186,000 miles a second) the mass would be infinite. Therefore, no 

 material body, as we know matter, can travel with the speed of 

 light. 13 Measurements on electrons emitted at high speeds from 

 radioactive elements indicate that those with velocities of 1 per cent 

 of the velocity of light (i.e., 1,860 miles per second) show no 

 appreciable increase in mass; at 50 per cent of the velocity of light 

 the mass increases 15 per cent, while at 99 per cent of the velocity 

 of light the electron showed more than seven times its mass when 

 at rest. 



Albert Einstein (Nobel prize, 1921) derived from his restricted 

 theory of relativity an equation similar to that of Lorentz. Ein- 

 stein also derived what is known as the mass-energy equation, 

 E = mc 2 , where E is the energy equivalent of mass, c the velocity 



