1875-1900+(gk)

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Becquerel was born in 1908 in France and won Nobel Prize winner for his part in discovering radioactivity. Becquerel was born into a family of gifted thinkers and notable scientists. In 1896, Becquerel wrapped a fluorescent substance, potassium uranyl sulfate, in photographic plates and black material in preparation for an experiment requiring bright sunlight. However, prior to actually performing the experiment, Becquerel found that the photographic plates were already exposed, showing the image of the substance. This discovery led Becquerel to investigate the spontaneous emission of nuclear radiation.

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Wilhelm Roentgen was born on March 27, 1845 it Lennep, Prussia. Roentgen's is well known for his discovery of x-rays in 1895. During an experiment with a glass vacuum tube with an electrical charge running through it, He noticed the invisible cathode rays caused a fluorescent effect on a screen covered with a film of barium platinocyanide. After speculating that a new form of rays were being emitted, he put his wife's in front of the tube and was able to take the first x-ray of her bone structure. In 1901 Roentgen was awarded the first Nobel Prize in Physics for his amazing discovery of the x-ray. He was a very modest man and refused to take out patents on his discovery because he did not want the rays to be named after himself. He died in 1923 of cancer that was believed to have not been related to his work with radiation. []

The model was proposed by JJ Thomson in 1904. The atom is made up of electrons surrounded by a soup of positive charge to balance the electron's negative charge. The concept is that the negatively charged plums are surrounded by a positively charged pudding. The atom is a sphere without moving parts. The electrons in this model are free to move and rotate within the pudding substance, but when an electron moved farther away from the center of the positive pudding, it became a larger net positive inward force. [] []