Examples of radioactive decay in the following topics:
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- Radioactive decay is a random process at the single-atom level; is impossible to predict exactly when a particular atom will decay.
- The following equation is used to predict the number of atoms (N) of a a given radioactive sample that remain after a given time (t):
- This relationship between the half-life and the decay constant shows that highly radioactive substances are quickly spent, while those that radiate weakly endure longer.
- A simulation of many identical atoms undergoing radioactive decay, starting with four atoms (left) and 400 atoms (right).
- Nuclear half-life is the time that it takes for one half of a radioactive sample to decay.
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- Radioactive decay occurs when an unstable atomic nucleus emits particles or light waves.
- Radioactive decay occurs when an unstable atomic nucleus loses energy by emitting energy in the form of emitted particles or electromagnetic waves, called radiation.
- Such isotopes are radioactive, and are referred to as "radioisotopes."
- The higher the energy, the more the particles or light produced by radioactive decay will penetrate a substance.
- In radioactive nuclei with too many neutrons, a neutron can be converted into an electron, called beta particle.
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- Radon gas, the result of radium's radioactive decay, can severely compromise indoor air quality.
- Radon is a dense, colorless, odorless noble gas that occurs naturally in the soil as the product of the radioactive decay of radium; it is a decay product of uranium and thorium, which occur naturally in the Earth's crust.
- Radon decays to form daughters, or decay products, which include radioactive polonium, lead, and bismuth.
- Radon is a gas, but these decay products are solids that can attach to dust and enter the lungs.
- Radon and its daughters continue to decay in the lungs, releasing alpha and beta particles that can damage cellular DNA and result in lung cancer.
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- Radioactive decay rate is exponential and is characterized by constants, such as half-life, as well the activity and number of particles.
- The decay rate of a radioactive substance is characterized by the following constant quantities:
- The mean lifetime (τ, "tau") is the average lifetime of a radioactive particle before decay.
- Total activity (A) is number of decays per unit time of a radioactive sample.
- Radioactivity is one very frequent example of exponential decay.
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- Radiometric dating is used to date materials using the decay rate of a radioactive isotope.
- In many cases, the daughter nuclide is radioactive, resulting in a decay chain.
- The mathematical expression that relates radioactive decay to geologic time is:
- Example of a radioactive decay chain from lead-212 (212Pb) to lead-208 (208Pb) .
- The final decay product, lead-208 (208Pb), is stable and can no longer undergo spontaneous radioactive decay.
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- In addition, problems will also often be given as word problems, so it is useful to know the various names of radioactively emitted particles.
- Describes how to write the nuclear equations for alpha and beta decay.
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- This occurs either through nuclear reactions in which an outside particle reacts with a nucleus, which can be supplied by a particle accelerator, or through radioactive decay, where no outside particle is needed.
- Nuclear transmutation was first consciously applied to modern physics by Frederick Soddy when he, along with Ernest Rutherford, discovered that radioactive thorium was converting itself into radium in 1901.
- Predicting the products of transmutation is like predicting the products of radioactive decay.
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- However, if neutron count surpasses an ideal ratio, a nucleus becomes unstable and can undergo radioactive decay.
- Only 90 isotopes in this region are believed to be perfectly stable, while 163 more are understood to be theoretically unstable but have never been observed to decay.
- Technetium and promethium, as well as elements of number 83 and above, have only isotopes that will decay over time.
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- Transuranium elements are those beyond uranium, none of which is stable because of radioactive decomposition.
- None of these elements is stable and each of them decays radioactively into other elements.
- They can also be created as common products of the decay of uranium and thorium.
- Each of these elements is radioactive, with a half-life much shorter than the age of the Earth.
- So, if any atoms of these elements were ever present at the Earth's formation, they have long since decayed.
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- The emission of these rays is called nuclear radioactivity, or simply radioactivity.
- A nucleus that spontaneously destroys part of its mass to emit radiation is said to decay.
- A substance or object that emits nuclear radiation is said to be radioactive.
- Uranium is radioactive whether it is in the form of an element or compound.
- Marie's radioactive fingerprints on some pages of her notebooks can still expose film.