Like Dissolves Like

Like dissolves like means that substances are more likely to dissolve in other substances with similar chemical properties. It is most often used when discussing polar and nonpolar solvents. For example, oil will not dissolve in water because oil is nonpolar and water is polar. Basically, a polar solvent will generally dissolve polar solutes and sometimes ionic solutes, and a nonpolar solvent will generally dissolve nonpolar solutes.