Radioactivity. Detection, shielding, dating and half-life
The online radioactivity simulations on this page will help you understand the basic principles of radioactivity and enlighten you on some of its most important associated concepts such as radioactive detection, radioactive shielding, radioactive dating and radioactive half-life.
This Thematic Unit is part of our Chemistry collection
STEM OnLine mini dictionary
Alpha Emission (α)
Type of decay where the nucleus emits a heavy particle composed of two protons and two neutrons (Helium-4 nucleus).
Beta Emission (β)
Nuclear process where a neutron transforms into a proton by emitting a high-energy electron or positron.
Gamma Radiation (γ)
Emission of high-frequency electromagnetic waves with high penetrating power that often accompanies alpha and beta processes.
Half-life
Time required for half of the nuclei in a radioactive sample to decay into a different element.
Natural Radioactivity
Phenomenon present in nature due to unstable isotopes existing in the Earth’s crust or produced by cosmic rays.
Nuclear Stability
Balance of forces within the nucleus that determines whether an atom will remain intact or undergo spontaneous decay.
Nuclide
Atomic species characterized by its number of protons and neutrons, and its nuclear energy state.
Radioactivity
Spontaneous process of decay of unstable atomic nuclei through the emission of particles and electromagnetic energy.
What is radioactivity
Radioactivity is the phenomenon by which some chemical elements, called radioisotopes, spontaneously emit radiation. This radiation can be in the form of alpha particles, beta particles, gamma rays or a combination of these types of radiation.
Radioactivity occurs due to the nuclear instability of certain atoms. The nuclei of these atoms are unstable and tend to decay, releasing energy in the form of radiation. This radiation can have ionizing effects, which means that it can release electrons from the atoms and molecules with which it interacts.
Applications of radioactivity
Radioisotopes are used in a variety of applications, such as in nuclear medicine for the diagnosis and treatment of disease, in industry for the inspection of materials, and in nuclear power generation.
Risks associated with radioactivity
Radioactivity can be dangerous to living beings if excessive exposure occurs or if radioactive materials are released into the environment in an uncontrolled manner. Prolonged exposure to ionizing radiation can have detrimental health effects, such as cell damage, genetic mutations and increased risk of developing cancer. Therefore, precautions must be taken and safety limits established to minimize exposure to radioactivity and protect people and the environment.
In the event of a nuclear or radiological incident, it is important to follow the directions of the authorities and evacuate or take protective measures as necessary. Regulatory agencies and nuclear safety programs are responsible for monitoring and regulating the use of radioactive materials to ensure the protection of public health and the environment.
STEM OnLine mini dictionary
Alpha Emission (α)
Type of decay where the nucleus emits a heavy particle composed of two protons and two neutrons (Helium-4 nucleus).
Beta Emission (β)
Nuclear process where a neutron transforms into a proton by emitting a high-energy electron or positron.
Gamma Radiation (γ)
Emission of high-frequency electromagnetic waves with high penetrating power that often accompanies alpha and beta processes.
Half-life
Time required for half of the nuclei in a radioactive sample to decay into a different element.
Natural Radioactivity
Phenomenon present in nature due to unstable isotopes existing in the Earth’s crust or produced by cosmic rays.
Nuclear Stability
Balance of forces within the nucleus that determines whether an atom will remain intact or undergo spontaneous decay.
Nuclide
Atomic species characterized by its number of protons and neutrons, and its nuclear energy state.
Radioactivity
Spontaneous process of decay of unstable atomic nuclei through the emission of particles and electromagnetic energy.
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Radioactivity simulations
Radioactivity detection
Radioactivity shielding
Half-Life I
In radioactivity, the half-life is the time interval required for half of the atomic nuclei in a radioactive sample to decay. If the half-life passes again, half of the remaining mass will remain (1/2, 1/4, 1/8, 1/16, 1/32, …) The mass gets smaller and smaller, but there is always a little bit left.
Half-Life II
Radioactivity dating
This simulation explains the concept of half-life, including the random nature of half-life, in terms of single particles and larger samples. It describes decay processes, including how elements change and emit energy and/or particles. Explains how radiometric dating works and why different elements are used for dating different objects. Also identifies that 1/2 life is the average time for a radioactive substance to decay.
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Isaac Newton
Joseph Louis Gay-Lussac
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Become a giant
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–
Become a giant
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Test your knowledge
What is radioactivity, and why is it a fundamental phenomenon for understanding the structure and stability of atomic nuclei?
How do the different types of radiation emitted during radioactive decay differ, and what does this imply for their interaction with matter?
Why are some elements radioactive while others are not? What makes a nucleus “decide” to break apart?
Is radioactivity always dangerous, or does it depend on the type and amount?
Why do radioactive materials take so long to stop emitting radiation? Shouldn’t they “run out” quickly?
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