How to tell if something is most soluble?

How to Tell Which Substance is Most Soluble

When trying to figure out which substance will dissolve best, the golden rule in chemistry is simple: like dissolves like. This means that substances with similar chemical properties and polarities will readily mix into one another.

To determine solubility, start by looking at the polarity of both the solute and the solvent. Polar and ionic substances—such as salt or sugar—tend to dissolve very well in polar solvents like water. On the flip side, nonpolar substances—like oils, fats, and waxes—will barely mix with water because water is too polar.

If you want to find the most soluble option in a given scenario, look for a matching pair. A nonpolar solute will always be most soluble in a nonpolar solvent like hexane, while a polar solute belongs in a polar solvent. Whenever the polarities align, the molecules interact strongly, resulting in high solubility.