Marie and her husband, French scientist Pierre Curie studied radioactive materials, particularly pitchblende, the ore from which uranium was extracted. They noticed that pitchblende was strangely more radioactive than the uranium extracted from it. While working in France at the time of Becquerel's discovery, Polish scientist Marie Curie became very interested in his work. It was not until the discovery of radium by the Curies two years later that interest in radioactivity became widespread. Only a few scientists were interested in Becquerel's findings. Uranium ore produces naturally occurring gamma radiation. Becquerel's discovery was, unlike that of the x-rays, virtually unnoticed by laymen and scientists alike. One of the minerals Becquerel worked with was a uranium compound. Henri Becquerel discovered this phenomenon while investigating the properties of fluorescent minerals. Some of the new research showed that certain types of atoms disintegrate by themselves. Many scientists of the period were working with cathode rays, and other scientists were gathering evidence on the theory that the atom could be subdivided. In 1896, French scientist Henri Becquerel discovered natural radioactivity. For his discovery of radioactivity, Becquerel was awarded the 1903 Nobel Prize for physics.Shortly after the discovery of x-rays, another form of penetrating rays was discovered. Today, we know uranium as one of the radioactive elements. This invisible something was named radiation, and it was determined that an element that gives off radiation is a radioactive element. Becquerel continued to test many samples of compounds and determined that the source of the invisible something was the element uranium. Becquerel concluded that the uranium compound gave off something invisible that could penetrate heavy paper and affect photographic film. In addition, he noticed that only the film that was in the drawer with the uranium compound had an image on it. He knew he had wrapped the film tightly in light proof paper, so the image was not due to stray light. Becquerel questioned what would have caused this. A couple of days later, he decided to develop this film anyway, and discovered an image of the uranium sample on the film. One day, after preparing the experiment, it was too cloudy to expose his samples to direct sunlight, so he stored the uranium compound and the film in a drawer. The experiment normally consisted of wrapping some photographic film in light proof paper, placing a piece of fluorescent uranium on top of the film, and leaving them in the sun. When working on the principles of fluorescence, he utilized photographic film to record fluorescence of various minerals when exposed to sunlight. While investigating the properties of fluorescent minerals, it was Becquerel who discovered that certain types of atoms disintegrate by themselves. Subsequent to Roentgen's discovery of X-rays, in 1896 a French scientist Henri Becquerel was experimenting with a uranium compound. Next, the discovery of radioactive elements
Explain what Becquerel found out about the element uranium.
Discuss why Becquerel earned the recognition of being awarded the 1903 Nobel Prize for physics.
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