Soluciones y Factores de Solubilidad

Solutions

Solutions are homogeneous mixtures containing two or more substances called the solute and solvent. The solute is the substance being dissolved, while the solvent is the substance in which the solute is dissolved. Solutions can exist in various states, such as gaseous, liquid, or solid.

Types of Solutions

Solutions are classified based on the states of the solution. For example:

• Gaseous solutions: These are solutions in which the solute and solvent are both gases. An example is carbon dioxide dissolving in air.
• Liquid solutions: In these solutions, the solute is a liquid, and the solvent is usually a liquid. An example is sugar dissolving in water.
• Solid solutions: These involve a solid solute and a solid solvent. An example is an alloy, where a metal solute is dissolved in a metal solvent.

Concentration Units

The concentration of a solution is a measure of how much solute is dissolved in a specific amount of solvent. Concentration can be expressed using various units, such as:

• Mass/mass percent: This unit indicates the percentage of the overall solution that is solute by mass.
• Volume/volume percent: This unit indicates the percentage of the overall solution that is solute by volume.
• Mass/volume percent: This unit indicates the percentage of the overall solution that is solute by mass dissolved in a specific volume of solvent.
• Parts per million (ppm): This unit is used to describe very small concentrations of a solute in a large volume of solvent.
• Parts per billion (ppb): This unit is used for even smaller concentrations of a solute in a large volume of solvent.
• Molarity: This unit is defined as the number of moles of solute per liter of solution and is a common concentration unit in the chemistry laboratory.
• Equivalents: This unit expresses concentrations in terms of moles of charge on ions.

Factors Affecting Solubility

Several factors can affect the solubility of a solute in a solvent, including:

• Temperature: As the temperature of the solvent increases, the solubility of most solid solutes in water generally increases. However, the solubility of gas solutes in water decreases with increasing temperature.
• Agitation: Stirring or agitating a solution can increase dissolving by bringing fresh solvent into contact with more solute.
• Surface area: Increasing the surface area of the solute can increase the rate of dissolving, as dissolving occurs at the surface of a solid.
• Pressure: For gas solutes, increasing the pressure of the gas above the solution can increase the solubility.

Solubility Rules

The solubility rules are a set of guidelines that help predict whether a solute will dissolve in a given solvent. These rules are based on the relationship between the solute and solvent and can be found on the back of the periodic table. For example, most non-metal compounds dissolve in water, while most metal compounds do not. Some exceptions to these rules exist, as certain metal compounds can dissolve in water or other solvents.