In the water treatment industry, we often hear about ions. Especially when we talk about ion exchange systems or ionically pure water. What does it mean and what exactly is an ion?
As mentioned above, ions are atoms or groups of atoms with an electrical charge (positive or negative). These electrical charges are created by the loss or gain of one or more electrons. Positively charged ions are called cations and negatively charged ions are called anions.
Specifically, an atom that loses an electron becomes a cation because its electric charge becomes positive and causes the ions to travel to the negative electrodes (cathode). In contrast, an atom that gains an electron becomes an anion. Typically, although there may be exceptions, metals form cations while nonmetals form anions.
How are the electrical charges of an atom or molecule changed?
In other words, what can change the electric charge of an atom or a molecule? Two ways are known for allowing the permutation of the electric charges of an atom. The first is by the combination of the atom with various other particles. The second way occurs when covalent bonds are broken so that the uniformity of electrons is broken.
What makes some ions more stable than others?
Simply put, the stability of ions comes from their valence. Briefly, valence refers to the number of bonds available on an atom, molecule or ion.
This means that valence is the binding capacity of atoms. Each atom, element or ion can have a valence of up to 8. The more electron pairs there are, the more stable the ion will be. In other words, when an ion has a valence of 8, its stability is at its maximum.