What is ionisation?

Ionisation is best defined as the process of losing or gaining electrons. When an atom gains or loses electrons, it transforms into an ion. This process can occur through various means, such as the absorption of energy or the interaction with radiation. For example, when ultraviolet light strikes an atom, it can impart enough energy to an electron, allowing it to escape the atom, resulting in a positively charged ion. Conversely, if an atom captures an electron, it becomes negatively charged.

Understanding ionisation is crucial in fields like physics and chemistry, as it plays a significant role in phenomena such as electrical conduction, chemical reactions, and radiation effects. The ability to create ions is also a fundamental aspect of certain types of radiation and their interactions with matter.