Seeking further confirmation of what he had found, he planned to continue his experiments. But the weather in Paris did not cooperate; it became overcast for the next several days in late February.
On March 1, he opened the drawer and developed the plates, expecting to see only a very weak image. Instead, the image was amazingly clear. The next day, March 2, Becquerel reported at the Academy of Sciences that the uranium salts emitted radiation without any stimulation from sunlight. Possibly he was motivated by simple scientific curiosity.
Or maybe he was simply impatient. Whatever his reason for developing the plates, Becquerel realized he had observed something significant. He did further tests to confirm that sunlight was indeed unnecessary, that the uranium salts emitted the radiation on their own. At first he thought the effect was due to particularly long-lasting phosphorescence, but he soon discovered that non-phosphorescent uranium compounds exhibited the same effect.
In May he announced that the element uranium was indeed what was emitting the radiation. Skip to main content. Nuclear Chemistry. Search for:.
Discovery of Radioactivity. Learning Objective Discuss the history of the discovery of radiation. Key Points The emission of the rays Becquerel discovered is called nuclear radioactivity, and the rays themselves are called nuclear radiation. A nucleus that spontaneously destroys part of its mass to emit radiation is undergoing radioactive decay.
Radiation does not vary with chemical state. She was a bright student who excelled in physics and math, like her father, who was a math and physics professor. While a brilliant and curious student, the University of Warsaw only admitted men and Curie was therefore unable to attend. Curie's sister, Bronya, also hoped to attend additional schooling. As such, they each worked to put the other through school, taking turns on who studied and who worked. In , after Bronya finished school, Curie moved to Paris.
There, she attended Sorbonne to study physics and mathematics. After years of schooling, Curie began her life and research in Paris. Curie received a commission to conduct research post graduation, and found lab space with Pierre Curie, a friend of a colleague. He was also a professor at Sorbonne. The Curies were married two years later. At the start of their relationship, Pierre and Marie worked on separate project, but after the birth of their first child, Pierre began to conduct research with Marie on x-rays and uranium.
She later discovered two new radioactive elements: Radium and Polonium which took her several years since these elements are difficult to extract and extremely rare. Unfortunately, the Curies died young.
Pierre Curie was killed in a street accident and Marie died of aplastic anemia, almost certainly a result of radiation exposure. Contributions: Ernest Rutherford is considered the father of nuclear physics. With his gold foil experiment he was able to unlock the mysteries of the atomic structure. He received the noble prize in chemistry in In at the University of Manchester, Rutherford was bombarding a piece of gold foil with Alpha particles.
Rutherford noted that although most of the particles went straight through the foil, one in every eight thousand was deflected back. He concluded that though an atom consists of mostly empty space, most of its mass is concentrated in a very small positively charged region known as the nucleus, while electrons buzz around on the outside.
Rutherford was also able to observe that radioactive elements underwent a process of decay over time which varied from element to element. In , Rutherford used alpha particles to transmutate one element Oxygen into another element Nitrogen. Papers at the timed called it "splitting the atom. We now have the essentials to utilize radioactive elements. Roentgen gave us x-rays, Becquerel discovered radioactivity, the Curies were able to discover which elements were radioactive, and Rutherford brought about transmutation and the "splitting of the atom.
Time showed the damaging effects of radiation exposure and the incredible destruction that could be harnessed from these elements. Radioactive isotopes are presently used in many aspects of human life today. Most people recognize radioactivity's contributions to industry, research and war, but it is even used within many peoples homes.
Here are a few examples of how radioactive isotopes are utilized today. Most people have radioactive material in their very own homes, or at least we would hope so. Because in most every smoke detector unit today there is a very small amount of Americium How does it work?
Well Americium is present in the detector in oxide form and it emits alpha particles and very low energy gamma rays. The alpha rays are absorbed in the detector, while the non-harmful gamma rays are able to escape.
The alpha particles collide with oxygen and nitrogen in the air of the detector's ionization chamber producing charged particles, or ions.
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