Everything is made of atoms, which are the smallest fundamental units of matter. Each atom has a centre called the nucleus, which contains protons and neutrons. Protons carry a positive charge, while neutrons are electrically neutral and help stabilise the nucleus by reducing the repulsive forces between protons.
Unlike protons and neutrons, electrons are located outside the nucleus but remain part of the atom. Electrons carry a negative charge and orbit the nucleus. Electrons are responsible for the atom's chemical properties.
Electrons and neutrons both interact with protons, but their roles differ:
- Inside the nucleus, neutrons are uncharged and help prevent protons from repelling each other by exerting nuclear forces.
- The nuclear force holds protons and neutrons together in the nucleus. Maintaining the right balance of protons and neutrons ensures the nucleus remains stable.
- Outside the nucleus, electrons interact with protons through their negative electric charge, balancing the overall charge of the atom.
- If an atom has too many or too few neutrons, it can become unstable and radioactive, undergoing decay by emitting radiation.
At our very core, we're all made of atoms. We're lights ourselves, because so much of what happens in our atoms involves electrons releasing energy as light.
- The light we observe is emitted when electrons within these atoms transition from higher to lower energy levels, releasing energy in the form of light.
With protons, neutrons, and electrons, an atom holds the key to life itself.