Atoms are electrically neutral because the number of protons and electrons in it are exactly the same. When an atom loses or gains an electron, it undergoes a process called ionization. Through ionization, an atom or a molecule acquires a positive or negative charge. This process often results in chemical changes and makes way for the formation of new chemical compounds. From table salts to fluorescent lamps, we owe a lot to the creation and disintegration of ionic bonds. There are a variety of instances in which ionization takes place. Certain components like the common salt (NaCl) separate themselves into ions when dissolved in water. This makes them an electrolyte. The most important factor of an electrolyte is that it conducts electricity. The process of passing electricity through an electrolyte to start off a chemical change is called electrolysis. ‘Lysis’ means to ‘Break up’ or ‘Dissolve’ in Greek and this process is often employed in metallurgical processes where pure metals are created from impure ores. In a salt electrolysis, the Sodium (Na) and Chloride (Cl) atoms split up as ions. Similarly in the electrolysis of water, the Hydrogen (H2) atom and the Oxygen (O) atom separate as ions.
Not all electrolytes are the same. Acids, bases and salts are all electrolytes. (i.e. their aqueous solution is capable of conducting electricity) But depending upon the rate of ionization and dissociation, electrolytes are classified into weak and strong electrolytes. For example, a strong acid like HydroChloric acid (HCL) disintegrates into ions almost completely and serves as an excellent conductor of electricity when dissolved in water. On the other hand, a weak acid like Ammonia (NH3) does not undergo full ionization when dissolved in water. This results in a situation wherein there are a small number of acetate ions and a much larger number of un-ionised molecules. An electrolyte such as this will not conduct electricity effectively. The equilibrium that exists between ionised and un-ionized components in these weak electrolytes is called an ionic equilibrium. Ionic equilibrium ionization and dissociation in polar solvents are integral factors in various chemical processes. For instance, in a chemical process like metal plating, the reactants are never fully converted to the desired products under an ionic equilibrium condition.
The pH scale is an important yardstick in Chemistry used to determine the relative acidity or alkalinity of solutions. Formulated by a Danish biochemist called S.P.L. Sorenson in 1909, the pH level gives us a measure of the concentration of [H+] ions in the solution. (pH denotes ‘Potential of Hydrogen). When the pH value of a given solution is higher than 7 it is considered alkaline or basic. Solutions with a pH value below 7 are considered acidic. The lower the pH value, the more acidic the solution. To give an example from everyday life, the pH value of vinegar is 4.0 and the pH value of lemon juice ranges between 2.0 to 3.0. Therefore, pH scale and acidity are interconnected. The pH value of an aqueous solution is also associated with it’s electrical conductivity.This is due to the fact that Hydrogen ions [H+] have great mobility and a sizable increase in their concentration increases the capability of the solution to conduct electricity.