Here's a breakdown:

* Solute: The substance that dissolves. It can be a solid, liquid, or gas.

* Solvent: The substance that dissolves the solute. It's usually a liquid, but can also be a solid or gas.

* Solution: The homogeneous mixture formed when the solute dissolves in the solvent.

Factors Affecting Solubility:

* Temperature: Solubility generally increases with temperature for solids and gases.

* Pressure: Solubility of gases increases with pressure.

* Nature of the Solute and Solvent: "Like dissolves like" - polar solutes dissolve in polar solvents (e.g., salt in water), and nonpolar solutes dissolve in nonpolar solvents (e.g., oil in gasoline).

* Presence of Other Substances: The presence of other solutes can affect the solubility of a given substance.

Examples of Solubility:

* Sugar in water: Sugar is soluble in water, meaning it dissolves and forms a homogeneous solution.

* Salt in water: Salt is also soluble in water, forming a salty solution.

* Oil in water: Oil is not soluble in water, as they are not miscible due to their different polarities.

Units of Solubility:

Solubility can be expressed in various units, including:

* g/100g solvent: grams of solute per 100 grams of solvent

* mol/L: moles of solute per liter of solvent (molarity)

* ppm: parts per million

Understanding solubility is crucial in many fields, including chemistry, biology, and environmental science. It helps us predict how substances will behave when mixed, design chemical reactions, and analyze environmental samples.