A solvent is a liquid, solid, or gas that dissolves another liquid, solid or gas. Examples of common solvents include nail polish, dry cleaning, spot removers, glue solvents and paint thinner.
When two substances dissolve into another, a solution is formed. This is opposed to two substances mixed together that are insoluble and one of them sinks to the bottom of the mixture like sand in water.
All of the ingredients are uniformly distributed in a solution; no residue is left in the bottom. Dissolving one compound into another is known as solubility. In addition to mixing, both substances in the solution interact with each other. When something is dissolved, molecules of the solvent arrange themselves around molecules of the solute. Heat is involved and entropy is increased making the solution more thermodynamically stable than the solute alone. Most organic solvents have a lower density than water, which means they are lighter and will form a separate layer on top of water. Solvents are classified into two categories: polar and non-polar.