The solute and solvent are the two components that, when mixed, generate a solution or solution. The solution is a homogeneous mixture, which can be liquid, gas or solid. In the case of liquid solutions, the solvent is a liquid, while the solute can be a substance in any of the physical states (liquid, gas or solid).
The solute is usually the minority component of a solution. We then say that the solute dissolves in the solvent or that the solvent dissolves the solute.
For example: lemonade is a solution. Since it is liquid and aqueous, its solvent is water. Meanwhile, the lemon juice and the sugar, which define its flavor, are the solutes, since we add them to the water to mix them and prepare the lemonade.
The solvent or solvent is the component where the solute dissolves . It is usually the majority component of solutions and the most common solvent is water.
The solvent is the component that defines whether a solution is liquid, gaseous or solid. A gaseous solution will have a gaseous solvent, and in the same way we have that solid solutions will have solid solvents.
Easy way to differentiate them
Generally, the solvent predominates over the solute : there is more solvent than solute. It makes sense, because it can happen that an excess of solute causes the solvent to become saturated, that it cannot dissolve more solute. In this case, we would no longer have a solution, but a mixture that is not homogeneous.
Even though the solute may sometimes be in a higher proportion (which is, for example, extremely soluble in the solvent), the state or material phase of the solution is defined by the solvent.
That is why in all juices, which are aqueous solutions, the solvent is water: juices are liquid because water, their solvent, is liquid. Also, the solvent is the component that dissolves the solute.
In a cup of milk chocolate, milk and powdered chocolate do not dissolve in water; if so, we would see the dust make the water disappear. Instead, the water turns a chocolatey color as the chocolate powder and milk begin to “disappear.” This means that the water, which is the solvent, has dissolved the chocolate and the milk, the solutes .
The solute therefore is the component that “disappears”, and that dissolves throughout the volume of the solvent.
Examples of solutes
Pigments and colorants
When pigments and dyes are dissolved in water or oil, colorful solutions are obtained. Since your crystals or granulated powder “disappear”, they are solutes, whether they are coloring liquids or glasses.
Salt dissolves in water to generate salty solutions. In the seas, salts are dissolved in huge volumes of water.
Sugar dissolves in water to generate sweet or sugary solutions. It is one of the best known solutes, as it is added to many drinks to sweeten them even more.
Oxygen, a gaseous solute, is dissolved in the air we breathe, always forming part of it in the atmosphere . It represents about 21% of the air.
Carbon dioxide, another gaseous solute, is also dissolved in the air, as well as in water to generate carbonated beverages (soda or soft drinks).
Ethylene glycol, a liquid solute, is added to water during antifreeze preparation.
Water vapor is also considered a gaseous solute, because when it is released from the boilers it will mix in the air with other gases.
Ethanol, a liquid alcohol, dissolves in water to generate alcoholic solutions. In beers, for example, water is the solvent, while ethanol, and other ingredients, are the solutes.
Sodium hypochlorite, a salt, dissolves in water to generate the famous bleaches or chlorinated solutions with which fabrics are bleached or surfaces are disinfected.
Examples of solvents
Water is capable of dissolving many substances, and being very abundant on Earth, it is considered the universal solvent. All solutions or fluids in living things are aqueous in nature.
In air, nitrogen is the main component or gas. It represents about 79% of the air. Therefore, it is the solvent of the air, where other gases such as oxygen, argon, carbon dioxide, among others, dissolve.
Carbon or other metals are added to cast iron in the steel formation process.
Similar to the nitrogen example, methane is the predominant gas in natural or cooking gas, which is why it is the solvent in that gas mixture or solution.
Mercury mixes with other metals in the formation of amalgams. It is therefore a black liquid and metallic solvent.
Acetone is another good example of a solvent, as it dissolves nail polish, or polyethylene foam.
Hexane is an organic solvent that is used for degreasing, and in the extraction of vegetable essences.
Toluene is another organic solvent with many industrial applications, ranging from gasoline and paint formulation to as a petroleum solvent .
Similar to how it happens with steel and iron, in bronze copper is the majority component. Therefore, in bronze, copper acts as the solvent, while tin is the solute. Likewise, in the brass alloy, copper is the solvent, this time zinc is the main solute.
Finally, in the previous section we saw ethanol as a solute. However, it can act as a solvent, as it also has the ability to dissolve some fats or organic substances.