Substance that is dissolved in another substance, called the solvent, to form a solution. The solute is usually present in a smaller amount compared to the solvent. Its role is fundamental in the formation of a solution, as it determines many of the chemical and physical properties of the mixture.

The solute can exist in various physical states: it can be a solid, such as table salt dissolved in water; a liquid, such as alcohol mixed with water; or a gas, such as carbon dioxide dissolved in soft drinks. In every case, it disperses at the molecular level within the solvent, creating a homogeneous mixture.

An important property of the solute is its solubility, which refers to the maximum amount that can be dissolved in a certain volume of solvent at a specific temperature. Another key characteristic is concentration, which indicates how much solute is present in the solution and can be expressed in various units, such as moles per liter or percentages by mass or volume.

The solute significantly influences the behavior of the solution: it alters the boiling point, the freezing point, and the osmotic pressure. In essence, the solute is the component that, when dissolved, allows the solution to acquire new properties compared to the pure solvent.