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TIIEORY OF ATOM atom, till they reach the same numbers as an atom of radium and thus, uranium is changed into radium. When again, their numbers are further reduced, the astonishing substance called radium is transformed into ordinary lead This transformation can also be brought about in some other elements in the laboratories In 1941, a scientist, Benjamin changed mercury into gold The atomic weight of mercury is 200 It was exploded with proton which was absorbed in the nucleus of the atom of mercury and its weight became 201 But this product was electrically unstable Eventually the nucleus emitted an alpha particle, the weight of which was 4. The result was, that the weight of the nucleus was now changed from 201 to 197, whuch is the atomic weight of gold
In 1953, experiments to change platinum into gold were successfully carried out in many laboratories The point, as to wbich element can easily or with difficulty be changed into which other element, may not have been fully experimented upon by the scientists, but in the field of science the change of one element into another is no longer a question of imagination only
The Three Stages of a Substance
Every Satom' is built-up of positively and negatively charged particles. The negative particle repulses any other particle approaching it.