What are ions? And how it …

An ion can be defined as a chemical species which holds a positive or negative charge of some magnitude.

Several methods exist for the preparation of ions. For example, spontaneous collisions between the molecules of a liquid or gaseous fluid can result in one of the electrons being knocked off an atom/molecule. This results in the formation of a positively charged ion and a free electron. This type of ionization is commonly referred to as physical ionization. The free-electron may even go on to attach itself to another atom or molecule, resulting in the formation of a new negatively charged anion.

Another important process through which ions can be created is through chemical interactions. For example, when an ionic compound such as salt is dissolved in a suitable solvent (such as water), the atoms that constitute the salt undergo dissociation and form free ions. When common salt, also known as sodium chloride, is dissolved in water, it undergoes dissociation to yield sodium cations and chloride anions. It can be noted that the sodium cations are denoted by the symbol Na⁺ and the chloride anions are denoted by the symbol Cl^–.