Chemical solutions. Concentration and molarity

Chemical solutions are homogeneous mixtures of two or more substances, where one of them is dispersed in the other, forming a dispersed phase and a dispersing phase. The dispersed phase is called the solute and the dispersing phase is known as the solvent. Solutions can be solid, liquid or gaseous, depending on the state of aggregation of the substances involved.

Solutions are of great importance in chemistry and in many aspects of our daily lives. For example, salt water is a common solution found in the oceans and seas. Also, many medicines are solutions in which the active ingredients are dissolved in a suitable solvent.

The amount of solute present in a solution is expressed in terms of concentration, which can be expressed as mass percentage, volume percentage, molarity, among others. The concentration of a solution can influence its physical and chemical properties, such as boiling point, melting point and electrical conductivity.

There are different ways of preparing a solution. The most common is the solid-liquid solution, where the solute is added to the solvent and stirred until it is completely dissolved. Liquid-liquid and gaseous-liquid solutions can also be prepared using techniques such as stirring, heating or using specific apparatus such as ultrasound.

Some solutions have special properties, such as saturated solutions, which contain the maximum amount of solute that can be dissolved in a given amount of solvent at a given temperature. If more solute is added, it will not dissolve and a precipitate will form. On the other hand, supersaturated solutions contain a larger amount of solute than can normally be dissolved, and are more unstable and can easily precipitate.