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THEORY OF ATOMI
69 Thulium. 70. Utrabium. 71 Lutangium. 72. Hafniunt. 73. Tantlum. 74. Tungsten 75. Rahanium. 76. Osmium. 77 Heridium 78. Platinum 79. Gold 80 Mercurry
81 Thalium 82. Lead. 83. Bismuth. 84 Pulomium. 85 Astanum 86 Radon 87. Francum. 88 Radium. 89 Octinium. 90 Thorium. 91 Protooctinium 92 Uranium.
FORMATION OF PRIMARY ELEMENTS Up to 1811, a molecule was considered to be the minutest indivisible elementary body, because it was believed up to that time that the elementary substances like gold, silver, iron etc cannot be transformed into another. A molecule of gold, silver etc, was considered to be the primary or elementary particle The famous scientist 'Avogadro' differentiated a molecule from an atom. For 86 years after that, the atom was considered to be the indivisible elementary particle The honour of making the first incision in the complicated operation of dissecting the delicate body of the atom belongs to the famous British Physicist, Sir J J Thomson, who in 1897, in the course of experiments, discovered a tiny particle which was very much smaller than the atom of hydrogen. This mysterious particle changed the whole conception about atomic
