Electrons are fundamental leptons with electric charge (-1e). They are stable, very light compared with protons and neutrons, and are essential to chemistry, electricity, and most everyday matter interactions.
In atoms
- Electrons occupy quantized energy states around atomic nuclei.
- When an electron changes from a higher to a lower energy state, the atom can emit a photon whose energy matches the level difference.
- The reverse process can absorb a photon and raise an electron to a higher state.
Wave–particle behavior
Like all quantum objects, electrons show both particle-like and wave-like behavior:
- They are detected as localized interaction events (particle-like).
- Their motion is described by a wavefunction and can show interference (wave-like).
Why they matter
- Chemical bonds and molecular structure are electron phenomena.
- Electric current is the organized motion of electrons in conductors.
- Many technologies (electronics, lasers, imaging, materials science) rely on controlling electron states.