A radioisotope is an isotope that has an unstable nucleus, making it radioactive. Radioisotopes are used in a variety of fields, including medicine, agriculture, and research. Radioisotopes can be man-made or occur naturally.
Man-made radioisotopes are produced in nuclear reactors. They are also made in particle accelerators, where atoms are bombarded with high-energy particles to create new and heavier elements. Some common man-made radioisotopes include technetium-99m (used in medical imaging), iodine-131 (used to treat thyroid cancer), and carbon-14 (used in radiocarbon dating).
Naturally occurring radioisotopes are found in the environment and in our bodies. They come from the decay of larger atoms into smaller ones. For example, uranium decays into thorium, which then decays into radium. Some natural radioisotopes are present at very low levels while others are much more abundant. The most common naturally occurring radioisotope is potassium-40, which makes up 0.012% of all potassium atoms. Other naturally occurringradioactive isotopes include uranium (found in rocks and soil), thorium (found in minerals), and radon (a gas that comes from the decay of radium).
Radioactivity was first discovered in 1896 by French physicist Henri Becquerel when he noticed that a sample of uranium salt caused a photographic plate to darken even when wrapped in paper to block out light exposure. This led to further investigation by Marie Curie who coined the term “radioactivity” and went on to discover two more radioactive elements: radium and polonium. In 1903, Curie and her husband Pierre were awarded the Nobel Prize for their work on radioactivity along with Becquerel who received honorable mention.
Today we know that there are three types of radiation emitted by radioactive materials: alpha particles, beta particles, and gamma rays. Alpha particles are massive compared to beta particles or gamma rays but have a relatively low amount of energy so they don’t penetrate far through matter before being stopped . Beta particles have less mass than alpha particles but more energy so they can penetrate further through matter before being stopped . Gamma rays have no mass but carry a large amount of energy so they can travel long distances through matter without being stopped . All three types of radiation can be harmful if not properly shielded against because they ionize atoms , damaging DNA which can lead to cancer .
Radioactive isotopes have many uses both inside and outside the body . In medicine , doctors may use them to diagnose certain conditions such as cancer or heart disease . Doctors may also use them to treat certain conditions such as thyroid cancer or blood disorders . Outside the body , scientists may use radioactive isotopes to study how chemicals react or interact with one another . They may also use them to date fossils or other objects .
Radioactive isotopes emit radiation while decaying into another element over time – this is called “decay.” The time it takes for half of a given sample of a particularradioactive isotopeto decay is known as its “half-life.” The longer the half-lifeof an isotope,the slower it decays; conversely, shorter half-lives indicate faster ratesof decay..