A saturated solution is a type of solution where the solute has dissolved to the maximum extent possible at a given temperature. This means that adding any more solute will not result in any further solute dissolving; instead, the excess solute will remain undissolved. The concentration of the solute in a saturated solution is at its highest possible value at that specific temperature. The state of the solute (solid, liquid, or gas) does not affect whether a solution is saturated or not.

A residue is the solid substance that is left behind after a separation process, such as evaporation, distillation, or filtration. It is the component that is not volatile (easily evaporated) or that is physically trapped by a filter. The residue is typically collected and can be further processed or analyzed. For example, after evaporating water from a salt solution, the salt would be the residue. After filtration, the solid particles trapped by the filter paper would be the residue.

A solvent is a substance that dissolves another substance to form a solution. It is typically the component present in the greater amount in a solution. The solvent molecules interact with the solute molecules, breaking apart the solute and dispersing it evenly throughout the solvent. This process allows the solute to be distributed at a molecular level within the solvent. Examples of common solvents include water, ethanol, and acetone.