Radioactive decay and binding energy

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Energy > Energy and forces > Radioactive decay and binding energy 

Radioactive decay is the process by which an unstable atomic nucleus loses energy by emitting radiation. The radiation can be alpha particles, electrons, positrons or finally photons. Radioactive decay is a spontaneous process and obeys the laws of quantum theory. Binding energy is the energy that holds an atomic nucleus together due to the strong nuclear force. Each element is described by a specific amount of binding energy. The higher binding energy correspond to more stable atomic nuclei. 

Connection to Big Idea about forces: The weak nuclear force is responsible for radioactive decay and transforming neutrons into protons, electrons and neutrinos. The strong interaction is what forms all particles (except the elementary ones) and keeps them together in nuclei. The energy stored through the strong energy is called binding energy.

Connection to Big Idea about the universe: Nuclear energy is generated in the interior of stars through nuclear fusion of elements. This is what powers a star throughout its life.

Connection to Big Idea about particles: Radioactive decay (that occurs spontaneously and nuclear fusion and fission (that change the binding energy of a system of particles) are phenomena occurring between microscopic particles.

Connection to Big Idea about quantum: Radioactive decays are obeying the laws of quantum mechanics. Under the description of classical physics radioactive decays couldn’t possibly occur.

Connection to Big Idea about Earth: The decay of radioactive elements inside Earth generates a lot of the Earth’s geothermal energy. Radioactive elements in rocks and fossils help the scientist to determine their age. Thus, based on them we get a better idea about the history and evolution of Earth. 

Subjects related: Chemistry, Physics

Age ranges: 12-13,13-14,14-15,15-16,16-17,17-18



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