Nuclear (8th and 9th grade)

Standard model of particle physics

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Physical and mathematical models

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Atoms can undergo processes that result in

[[$\alpha$]] radiation, which gives out helium-4 nucleii (which are bundles of two protons and two neutrons)
[[$\beta^-$]] radiation, which gives out an electron and an antineutrino (the antiparticle of a neutrino)
[[$\beta^+$]] radiation, which gives out a positron (antiparticle of an electron) and a neutrino
[[$\gamma$]] radiation, which gives out photons (particles of electromagnetic radiation) of high energy

Fun fact: if a particle (like an electron) meets up with its antiparticle (a positron), both particles get annihilated, resulting in energy
[[$$E = 2mc^2$$]]
In the case of an electron and a positron, the energy released by this annihilation is of around [[$8\cdot 10^{-14}$]]. So, a gram of electrons and positrons being annihilated equals [[$4\cdot 10^{26}$]] joules of instant energy.

The amount of atoms [[$\Delta N$]] undergoing nuclear reactions in a unit of time [[$\Delta t$]] is proportional to the amount [[$N$]] of atoms that have not reacted yet. Mathematically:
[[$$\frac{\Delta N}{\Delta t} = -\lambda N$$]]
for a constant [[$\lambda$]].

Modern-day alchemy

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Once upon a time, alchemists claimed to be able to turn inexpensive metals into gold.

Modern-day physicists are not able to do so either. However, thanks to our contemporary understanding of the Fundamental interactions, we are able to predict how different substances themselves undergo shapeshifter-like changes to become other substances. The secret agents in this process is the weak interaction. Take a look at the weak interaction!

The result is nuclear radiation, given by atoms that change the properties of their nucleii. The following diagram is a short recap of how the Periodic table of elements works and what atoms can be thought of looking like.