Discrete Energy and Radioactivity

Discrete Energy

Discrete energy levels refer to the fact that atoms can only contain specific, quantified energy levels. This is also known as the Quantum Theory.
The energy level difference corresponds to the energy of the photon that is emitted or absorbed.
Each element has its own unique set of energy levels, which can be represented with energy level diagrams.
When an atom gains energy (e.g. by absorbing a photon), an electron may jump to a higher energy level. This is called excitation.
When an electron falls from a higher energy level to a lower one, it loses this energy by emitting a photon, following the principle of de-excitation.
The colour of the light emitted corresponds to the frequency (and hence energy) of the emitted photon.

Radioactivity is the process by which unstable atomic nuclei lose energy by emitting radiation.
There are three types of radioactive decay: alpha, beta, and gamma.
Alpha Decay: An alpha particle (which is essentially a helium nucleus, with 2 protons and 2 neutrons) is emitted from the nucleus, resulting in the creation of a new element, emitting an alpha particle.
Beta Decay: Involves the transformation of a neutron into a proton, resulting in the emission of an electron-like particle known as a beta particle.
Gamma Decay: Usually occurs after an alpha or beta decay, as the daughter nucleus moves to a lower energy state by emitting a gamma photon.
Each type of radioactive decay is not only accompanied by the release of particles but also involves the release of energy, further emphasizing the principle of discrete energy levels.
Radioactive substances have half-lives, a term referring to the time required for half of the substance to decay.
Applications of radioactivity include medical imaging, cancer therapy, and nuclear power generation.